Previous APMS Colloquia
Fall 2020
Thursday, November 5, 4:00-5:00 pm, on Zoom
Prof. John Rogers (Northwestern University)
- Louis Simpson and Kimberly Querrey Professor of Materials Science and Engineering
- Biomedical Engineering and Neurological Surgery
Skin-Like Wireless Wearables –
From Premature Babies in the NICU to Patients with COVID-19
Abstract: Recent global events are reshaping the geopolitical and socio-economic landscape in ways that will likely alter research priorities for at least a generation – a broad consensus is that long-term solutions to the underlying societal challenges will only occur through innovative technologies and advanced medicines, as life-saving diagnostics, digital biosensors, therapeutics and preventatives. This talk will outline work that intersects with essential unmet needs in this broader context, specifically in the form of skin-like wireless wearables for continuous monitoring of physiological status with clinical-grade precision. The focus is on foundational ideas in materials, design and manufacturing, with examples of devices designed for patient populations that range from premature babies in neonatal intensive care units to COVID-19 patients in the hospital and the home – both deployed locally within the medical complex here in Chicago and globally in clinics across lower and middle income countries in Africa and Central America.
Bio: Professor John A. Rogers obtained BA and BS degrees in chemistry and in physics from the University of Texas, Austin, in 1989. From MIT, he received SM degrees in physics and in chemistry in 1992 and the Ph.D. degree in physical chemistry in 1995. From 1995 to 1997, Rogers was a Junior Fellow in the Harvard University Society of Fellows. He joined Bell Laboratories as a Member of Technical Staff in the Condensed Matter Physics Research Department in 1997, and served as Director of this department from the end of 2000 to 2002. He then spent thirteen years on the faculty at University of Illinois, most recently as the Swanlund Chair Professor and Director of the Seitz Materials Research Laboratory. In the Fall of 2016, he joined Northwestern University as the Louis Simpson and Kimberly Querrey Professor of Materials Science and Engineering, Biomedical Engineering and Medicine, with affiliate appointments in Mechanical Engineering, Electrical and Computer Engineering and Chemistry, where he is also Director of the recently endowed Querrey Simpson Institute for Bioelectronics. He has published more than 750 papers, is a co-inventor on more than 100 patents and he has co-founded several successful technology companies. His research has been recognized by many awards, including a MacArthur Fellowship (2009), the Lemelson-MIT Prize (2011), the Smithsonian Award for American Ingenuity in the Physical Sciences (2013), the MRS Medal (2018) and most recently the Benjamin Franklin Medal from the Franklin Institute (2019). He is a member of the National Academy of Engineering, the National Academy of Sciences, the National Academy of Medicine, the National Academy of Inventors and the American Academy of Arts and Sciences.
Sponsored by: Department of Applied Physics and Materials Science (APMS) & Center for Materials Interfaces in Research and Applications (¡MIRA!)
Thursday, October 29, 4:00-5:00 pm, on Zoom
Dr. Badri Bhattarai (NAU)
Chemistry and Structure of Noble Metal Nanoclusters
Abstract: Metal nanoparticles of size less than 3 nm, also known as nanoclusters, exhibit molecular properties, that have been extensively studied for use in applications in a diverse range of fields such as optoelectronics, catalysis, sensing, etc. due to their unique properties that arise as a result of their dimensions. Nanoclusters are excellent model systems to study the chemistry of nanomaterials at the molecular level as their molecular formula, crystal structure, chemical composition, electronic structures, etc. can be experimentally measured and theoretically calculated. In addition, knowledge of their thermodynamic stability and mechanisms of formation can be leveraged in developing green and safer synthetic routes. In this talk, I will mostly present from my publications on nanoclusters research. Even though nanoparticle research is more focused on the end product of the synthesis and their properties, rather than the process, I will show how a nanoparticles synthesis could be dismantled which became very useful in developing a green synthetic route with significant process efficiency. I will also discuss briefly on the chemistry of alloying of metal nanoclusters and their structures.
Bio: Badri Bhattarai is currently a postdoctoral scholar at the Center for Materials Interfaces in Research and Applications (¡MIRA!), Department of Applied Physics and Materials Science, Northern Arizona University. He received an MS in Chemistry from Tribhuvan University, Nepal in 2012 and nanoparticles synthesis, post-synthetic modifications of metal core and surface ligands, and study of greener synthetic routes. This work won several awards, including the American Chemical Society Ciba Green Chemistry Award. Immediately after graduating in 2018 with a Ph.D., he served as a Co-Technical lead for a national NSF I-Corps program (2018 Fall Atlanta Cohorts) to prototype and study the business aspect of silver- based antimicrobial coating technology. He took a short postdoctoral research associate position in 2019 at the Department of Chemistry, Old Dominion University, Virginia where his research focus was on the surface functionalization of plasmonic silver nanoparticles for drug delivery, sensing and imaging applications. He joined Northern Arizona University in June 2020 as a postdoctoral scholar. His current research interests include synthesis and study of DNA-templated noble metal nanoclusters, monolayer protected noble metal nanoclusters, and functionalization of such nanoclusters. He has 8 scientific papers from his graduate research.
Thursday, October 22, 4:00-5:00 pm, on Zoom
Prof. Jim Werner (Los Alamos Nat’l Laboratory)
- Center for Integrated Nanotechnologies
Methods to Visualize 3D Dynamics
Abstract: As humans, most of the information we acquire about the outside world comes from our visual senses. Seeing truly is believing. However, in many aspects of science, information is reduced to symbol or line plots on a Cartesian coordinate system. Imaging and microscopy methods are different, often leading to the visualization and understanding of richer and more complex interactions. However, imaging and microscopy methods are generally limited to two dimensions (the XY plane of the microscope used for observation). This talk will focus on methods for visualizing 3D dynamics of fluorescent species. It will discuss single-molecule/single particle 3D tracking methods using both camera-based approaches and methods based upon modified confocal microscope geometries that employ active feedback. Methods of rapidly scanning cell-sized volumes (tens of microns cubed) in 3D, such as selective plane illumination microscopy using swept Bessel beams or lattice light sheet excitation, will also be discussed.
Bio: Jim Werner is currently a technical staff member in the Center for Integrated Nanotechnologies at Los Alamos National Laboratory (LANL). He received a BS in Applied Physics from Caltech in 1992 and earned a Masters and Ph.D. in Applied Physics from Cornell University, where he was a Hertz Foundation Fellow. He came to Los Alamos National Laboratory near the end of 1997 as postdoctoral research associate working on efforts to sequence DNA by single molecule detection methods. He converted to a staff scientist position in 2001 in the Bioscience Division of LANL and became a member of the Center for Integrated Nanotechnologies in 2006. From October of 2016 till October of 2020, Werner held various management positions within the Center for Integrated Nanotechnologies, primarily serving as a Deputy Group Leader. His research interests include single molecule biophysics, novel optical instrument development, and laser spectroscopy. Werner is an author/co-author of >70 scientific papers, has received two R&D 100 Awards, and became a Fellow of the American Physical Society in 2016.
Thursday, October 15, 4:00-5:00 pm, on Zoom
Prof. Anthony Hoffman (Univ. of Notre Dame)
- Department of Electrical Engineering
Localized Optical Modes on Epsilon-Near-Zero Materials and Metasurfaces
Abstract: Throughout the past several decades, scientists and engineers have explored emergent optical behavior and new optical devices derived from materials with unusual optical properties, such as a negative index of refraction or hyperbolic dispersion. These novel optical properties have been demonstrated using naturally-occurring materials and engineered using nanophotonics. Interest in such materials has grown steadily as they promise highly-desired optical characteristics for applications in super-resolution imaging, enhanced spontaneous emission, and extreme sub- diffraction optical confinement and guiding. In this talk, I will present my group’s recent work on long-wavelength epsilon-near-zero (ENZ) materials using polar dielectrics. I will show how optical antennas fabricated on ENZ materials exhibit multi-mode monochromatic behavior and how the far-field of these antennas can be drastically altered via the antenna length. I will also discuss our recent work on structured illumination imaging that leverages hyperbolic dispersion in engineered silver metasurfaces.
Bio: Anthony Hoffman is an associate professor in the Department of Electrical Engineering at the University of Notre Dame where he directs the Notre Dame Nanophotonics Group. Hoffman is assistant chair of the Electronics, Photonics, Materials, and Devices group in the department. He serves as an associate editor for Optics Express and is the IEEE Calumet EDS/PHO Chair. Prior to joining Notre Dame, Hoffman earned the M.A. and Ph.D. degrees from Princeton University, where he was awarded the Charlotte Elizabeth Proctor Honorific Fellowship in recognition of his work. After joining Notre Dame, Hoffman received the NSF CAREER Award and the Department of Electrical Engineering Teaching Award.
Thursday, October 8, 4:00-5:00 pm, on Zoom
Prof. Nathan Mara (University of Minnesota)
- Department of Chemical Engineering and Materials Science
Breaking Bad:
Interface driven deformation and fracture at the nanoscale
Abstract: Richard Feynman in his famous 1959 lecture described the potential for atomic-scale manipulation of matter and the fantastic control over material performance that could result. Today, this potential has been realized through advancements in materials synthesis, simulation, characterization, and property measurement. In this vein, I will present two recent examples where atomic scale defect/interface interactions profoundly influences the mechanical performance of materials: (1) Nanolayered composites and (2) Prediction of multiscale fracture behavior.
(1) As a result of their high interface content and atomic-level interfacial structure, nanolayered materials exhibit an order of magnitude increase in strength, greater thermal stability, and enhanced radiation damage resistance in comparison to their coarse-grained counterparts. We investigate Cu-Nb nanolayered composites produced via two routes: Accumulative Roll Bonding and Physical Vapor Deposition. These methods produce composites where the crystallographic textures and atomic-level interfacial structures can be tightly controlled, and their effects on strength and failure carefully evaluated.
(2) Due to pronounced effects of sample size, a major challenge persists in correlating microscale measurements to macroscale measurements, especially for ductility and fracture. I will discuss the challenges of diminished sample size inherent to evaluating fracture behavior at the microscale, and the possibilities of using micro-scale testing and knowledge of atomic-level deformation mechanisms to predict the Ductile-to-Brittle Transition (DBT) in Si and W. The DBT will be used to benchmark micro-scale to bulk-scale fracture behavior, and discussed in terms of the interplay of sample size and the onset of increasing plasticity with temperature.
Bio: Dr. Nathan Mara arrived at the University of Minnesota as an Associate Professor in November 2017 from the Center for Integrated Nanotechnologies (CINT) at Los Alamos National Laboratory (LANL). There, he was a deputy director of the Institute for Materials Science at LANL, and Thrust Leader for the Nanoscale Electronics and Mechanics thrust at CINT. His research focuses on the relationship between microstructure and mechanical behavior at the nanoscale, with an emphasis on structural applications in extreme environments such as high temperature, stresses, strain rates, and radiation environments. Dr. Mara is the past chairman (chair 2013-2015) of the Nanomechanical Materials Behavior Committee of The Minerals, Metals & Materials Society (TMS,) and has published ~150 peer-reviewed journal articles spanning topics from synthesis of bulk nanocomposites to performance of advanced materials under extreme conditions. He received the TMS Young Leader’s Professional Development Award in 2012, the LANL Distinguished Mentor Performance Award in 2010 for his dedication to undergraduate and graduate research.
Thursday, October 1, 4:00-5:00 pm, on Zoom
Prof. Zhenan Bao (Stanford University)
- K.K. Lee Professor of Chemical Engineering
- Director, Stanford Wearable Electronics Initiative Stanford University
Skin-Inspired Organic Electronics
Abstract: Skin is the body’s largest organ, and is responsible for the transduction of a vast amount of information. This conformable, stretchable, self-healable and biodegradable material simultaneously collects signals from external stimuli that translate into information such as pressure, pain, and temperature. The development of electronic materials, inspired by the complexity of this organ is a tremendous, unrealized materials challenge. However, the advent of organic-based electronic materials may offer a potential solution to this longstanding problem. In this talk, I will describe the design of organic electronic materials to mimic skin functions. These new materials and new devices enabled arrange of new applications in medical devices, robotics and wearable electronics.
Bio: Zhenan Bao is Department Chair and K.K. Lee Professor of Chemical Engineering, and by courtesy, a Professor of Chemistry and a Professor of Material Science and Engineering at Stanford University. Bao founded the Stanford Wearable Electronics Initiative (eWEAR) in 2016 and serves as the faculty director. Prior to joining Stanford in 2004, she was a Distinguished Member of Technical Staff in Bell Labs, Lucent Technologies from 1995-2004. She received her Ph.D in Chemistry from the University of Chicago in 1995. She has over 500 refereed publications and over 65 US patents with a Google Scholar H-Index >160. Bao is a member of the National Academy of Engineering and the National Academy of Inventors. She is a Fellow of MRS, ACS, AAAS, SPIE, ACS PMSE and ACS POLY. Bao was selected as Nature’s Ten people who mattered in 2015 as a “Master of Materials” for her work on artificial electronic skin. She was awarded the inaugural ACS Central Science Disruptor and Innovator Prize in 2020, the Gibbs Medal by the Chicago session of ACS in 2020, the Wilhelm Exner Medal by Austrian Federal Minister of Science 2018, ACS Award on Applied Polymer Science 2017, the L’Oréal-UNESCO For Women in Science Award in the Physical Sciences 2017, the AICHE Andreas Acrivos Award for Professional Progress in Chemical Engineering in 2014, ACS Carl Marvel Creative Polymer Chemistry Award in 2013, ACS Cope Scholar Award in 2011, the Royal Society of Chemistry Beilby Medal and Prize in 2009, the IUPAC Creativity in Applied Polymer Science Prize in 2008. Bao is a co-founder and on the Board of Directors for C3 Nano and PyrAmes, both are silicon-valley venture funded start-ups. She serves as an advising Partner for Fusion Venture Capital.
Thursday, September 24, 4:00-5:00 pm, on Zoom
Prof. Atul N. Parikh (University of California, Davis)
Mixing Water, Transducing Energy, Shaping Membranes: Autonomously Self-regulating Giant Vesicles
Abstract: A solute, excluded from or confined within a spatial “compartment” embedded in an aqueous continuum, creates a gradient in the chemical activity of water. This in turn prompts a directed flow of water pushing it into the solute-laden compartment and out of the solute-starved one. Serving as a non-specific entropic force, this osmotic stress acts on the vesicular boundaries producing long-lived out-of-equilibrium morphologies and cooperative behaviors.
Drawing from recent experiments in our lab employing giant vesicles containing (or excluding) molecular (e.g., sugars) and colligatively non-ideal macromolecular (e.g., PEG and Dextran) osmolytes, this talk considers how the osmotic activity of water dynamically remodels the membrane, inducing membrane shapes (including protrusions, invaginations, and buds), driving topological transitions (producing colonies of daughter vesicles), and orchestrating liquid-liquid phase separations – all while dissipating the osmotic energy in theoretically predictable manners. Comparing these processes as elemental events in the homeostatic working of a living cell, these findings support the idea that water is not a mere solvent for life – a blank canvas on which biomolecules become animated – but an active medium that guides organization and dynamics of biomolecules in complex, subtle and essential ways.
Bio: Atul N. Parikh is a member of the faculty of Biomedical Engineering at the University of California, Davis (2001-present). He received his B. Chem. Eng. Degree from the University of Bombay (1987) and Ph.D. degree from the Department of Materials Science & Engineering at the Pennsylvania State University (1993). Between 1996 and 2001, he served as a postdoctoral scholar and then as a technical staff member in the Chemical Science and Bioscience divisions at Los Alamos National Laboratory (LANL).
His research interests include biomolecular materials, self-assembly and self-organization, membrane biophysics, synthetic chemical biology, and origins of life. Parikh can be reached by e- mail at anparikh@ucdavis.edu
Thursday, September 17, 4:00-5:00 pm, on Zoom
Prof. Marko Lončar (Harvard University)
John A. Paulson School of Engineering and Applied Sciences
New Opportunities with Old Optical Materials
Abstract: Lithium niobate (LN) is an “old” material with many applications in optical and microwave technologies, owing to its unique properties that include large second order nonlinear susceptibility, large piezoelectric response, and wide optical transparency window. Conventional discrete LN components, the workhorse of the optoelectronic industry for many decades, are reaching their limits, however. I will discuss our efforts aimed at the development of integrated LN photonic platform, featuring strong light confinement and dense integration, that has the potential to revolutionize optical communication networks and microwave photonic systems, as well as enable realization of quantum photonic circuits. Examples include high bandwidth, low voltage, and low loss electro-optic (EO) modulators [1], EO frequency combs [2], and programmable “photonic molecules” [3]. Devices that benefit from LN’s strong second and third order nonlinearity, including second harmonic generators [4] and Kerr frequency combs [5], will also be discussed.
Diamond is another “old” material with remarkable properties! It is transparent from the ultra-violet to infrared, has a high refractive index, strong optical nonlinearity and a wide variety of light-emitting defects of interest for quantum communication, computation and sensing. In my talk, I will discuss our recent efforts focused on the control of the negatively charged silicon vacancy (SiV) color center in diamond using nanomechanics. Examples include the enhancement [6] and coherent control [7] of SiV electron spin, and reduction of spectral diffusion and inhomogeneous broadening [8] of SiV centers.
- C. Wang, M. Zhang, X. Chen, M. Bertrand, A. Shams-Ansari, S. Chandrasekhar, P. Winzer, and M. Lončar. “Integrated lithium niobate electro-optic modulators operating at CMOS-compatible voltages.” Nature, 562, 101 (2018)
- M. Zhang, B. Buscaino, C. Wang, A. Shams-Ansari, C. Reimer, R. Zhu, J. Kahn, and M. Loncar. “Broadband electro-optic frequency comb generation in an integrated microring resonator.” Nature, 568, 373(2019)
- M. Zhang, C. Wang, Y. Hu, A. Shams-Ansari, T. Ren, S. Fan, and M. Lončar. “Electronically Programmable Photonic Molecule.” Nature Photonics, 13, 36 (2019)
- C. Wang, C. Langrock, A. Marandi, M. Jankowski, M. Zhang, B. Desiatov, M. M. Fejer, and M. Lončar. “Ultrahigh-efficiency wavelength conversion in nanophotonic periodically poled lithium niobate waveguides.” Optica, 5, 1438 (2018)
- C. Wang, M. Zhang, M. Yu, R. Zhu, H. Hu, and M. Loncar, “Monolithic lithium niobate photonic circuits for Kerr frequency comb generation and modulation.” Nature Communications, 10, 978 (2019)
- Y. I. Sohn*, S. Meesala*, B. Pingault*, H. A. Atikian, J. Holzgrafe, M. Gündoğan, C. Stavrakas, M. J. Stanley, A. Sipahigil, J. Choi, M. Zhang, J. L. Pacheco, J. Abraham, E. Bielejec, M. D. Lukin, M. Atatüre, and Marko Lončar. “Controlling the coherence of a diamond spin qubit through its strain environment.” Nature Communications, 9, 2012 (2018)
- S. Maity, L. Shao, S. Bogdanović, S. Meesala, Y. I. Sohn, N. Sinclair, B. Pingault, M. Chalupnik, C. Chia, L. Zheng, K. Lai, and M. Lončar “Coherent Acoustic Control of a Single Silicon Vacancy Spin in Diamond.” arXiv:1910.09710v2 (2019)
- B. Machielse, S. Bogdanovic, S. Meesala, S. Gauthier, M. J. Burek, G. Joe, M. Chalupnik, Y. I. Sohn, J. Holzgrafe, R. E. Evans, C. Chia, H. Atikian, M. K. Bhaskar, D. D. Sukachev, L. Shao, S. Maity, M. D. Lukin, and M. Loncar. Submitted. “Electromechanical Control of Quantum Emitters in Nanophotonic Devices” Physical Review X, 9, 031022 (2019).
Bio: Marko Lončar is Tiantsai Lin Professor of Electrical Engineering at Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), as well as Harvard College Professor. Lončar received his PhD from Caltech in 2003. After completing his postdoctoral studies at Harvard, he joined SEAS faculty in 2006. Lončar is expert in nanophotonics and nanofabrication, and his current research interests include quantum and nonlinear nanophotonics, quantum optomechanics, and nanofabrication. He is recipient of Sloan Fellowship (2010) and Levenson Prize for Excellence in Undergraduate Teaching (2012). Lončar is fellow of Optical Society of America, and Senior Member of IEEE and SPIE. He is co-founder and Chief Scientific Adviser at HyperLight Corporation.
Thursday, September 10, 4:00-5:00 pm, on Zoom
Dr. John Gamble (Microsoft Quantum)
Principal Quantum Engineering Manager
Toward large-scale engineering models for qubits
Abstract: As a field, quantum computing is rapidly progressing from exciting basic science to production engineering. However, actually designing and building the quantum bits – qubits – that power a quantum computer is a daunting engineering task, as small details of the design can have large impacts on device operation. In this talk, I discuss the application of large-scale engineering approaches to two promising scalable qubit platforms: semiconductor quantum dots and Majorana nanowires. After introducing these qubit platforms, I will present our computational approach simulates the physics of these devices from the CAD schematics used for fabrication. By systematically varying device geometry parameters, we perform high-throughput computations to probe vast swaths of parameter space. We combine compressed sensing ideas from signal processing with these automatic simulations to tune up and optimize qubit designs in an extensible way, demonstrating much better scaling than previous approaches. We then discuss techniques for defeating the “curse of dimensionality” that occurs in design optimization. By adapting a combination of Latin hypercube sampling and Gaussian process regression (as has been applied in, e.g., aeronautical engineering), we show a path forward to navigating an intricate, high-dimensional, design optimization space. The techniques presented here are surprisingly general and apply equally to a large number of problems across the physical sciences. Just as importantly, robust, open-source packages have proliferated recently, so that interested audience members can readily try out the techniques I discuss on their own research problems.
Bio: John Gamble (pronouns he/him/his) is currently Principal Quantum Engineering Manager at Microsoft Quantum, where he leads a team of engineers working to model and optimize qubits, working in continuous and close collaboration with theorists and experimentalists around the world. His work mainly focuses on the theory and practical design of physical quantum systems, developing and deploying large-scale computer-aided engineering tools to understand and refine qubits. He currently works on semiconductor and hybrid superconductor-semiconductor qubits, such as topological nanowires, quantum dots, and semiconductor impurities, drawing heavily on condensed matter physics, electrical engineering, quantum information science, and quantum chemistry.
Thursday, September 3rd, 4:00-5:00 pm, on Zoom
Prof. Akif Tezcan (University of California San Diego)
Chemical Design of Functional Protein Assemblies
Abstract: Proteins represent the most versatile building blocks available to living organisms or the laboratory scientist for constructing functional materials and molecular devices. Underlying this versatility is an immense structural and chemical heterogeneity that renders the programmable self-assembly of proteins an extremely challenging design task. To circumvent the challenge of designing extensive non-covalent interfaces for controlling protein self-assembly, we have endeavoured to use bonding strategies based on fundamental principles of inorganic, supramolecular and polymer chemistry. These strategies have resulted in discrete or periodic protein architectures that display high structural order over large length scales and possess emergent chemical/physical/functional properties. In this talk, I will present some of the recent protein-based assemblies and materials constructed in our laboratory.
Bio: Akif Tezcan was born and raised in Istanbul, Turkey. He received his B.A. degree in chemistry from Macalester College (St. Paul, MN), and his Ph.D. degree from Caltech (Pasadena, CA), where he worked with Harry Gray and Jay Winkler on the folding and redox properties of metalloproteins. He continued his studies at Caltech as a postdoctoral fellow in Doug Rees’ group, where he focused on structural investigations of nitrogenase complexes. He has been at UCSD since 2005, where he is currently Professor of Chemistry, Biochemistry and Materials Science and Leslie Orgel Faculty Scholar. His group’s research focuses using chemical tools and principles to address biological questions and to create new biological materials.
Thursday, August 27th, 4:00-5:00 pm, on Zoom
Prof. Chandralekha Singh (University of Pittsburgh)
President, American Association of Physics Teachers
Director, Discipline-based Science Education Research Center
Department of Physics and Astronomy
How to Enhance Physics by Making it INCLUSIVE
Abstract: Instructors often only focus on content and pedagogical approaches to improve student engagement and learning in physics courses. However, students’ motivational characteristics can also play an important role in their engagement and success in physics. For example, students’ sense of belonging in a physics class, their self-efficacy, and views about whether intelligence in physics is “fixed” or “malleable” can affect engagement and learning. These types of concerns can especially impact the learning outcomes of women and racial/ethnic minority students and stereotype threats can exacerbate these issues. In this colloquium, I will discuss prior research studies that show how different types of social psychological interventions (e.g., social belonging and growth mindset) have improved the motivation and learning outcomes of all students, especially women and underrepresented minorities in STEM fields. These interventions include providing data to students about how intelligence is malleable and one can become an expert in a discipline by working hard in a deliberate manner, sharing with students examples of testimonies of past students with diverse backgrounds who struggled initially but then succeeded by working hard and using deliberate practice. I will discuss how these ecological interventions were adapted and implemented in our physics classes. The types of interventions are short, requiring less than one hour of regular class time even though they have the potential to impact student outcomes significantly—especially for women and other underrepresented students in physics classes.
Bio: Chandralekha Singh is a professor in the Department of Physics and Astronomy and the Founding Director of the Discipline-based Science Education Research Center (dB-SERC) at the University of Pittsburgh. She is currently the President of the American Association of Physics Teachers. She obtained her undergraduate degree in physics from the Indian Institute of Technology Kharagpur and her Ph.D. in theoretical condensed matter physics from the University of California Santa Barbara. She was a postdoctoral fellow at the University of Illinois Urbana Champaign, before joining the University of Pittsburgh. She has been conducting research in physics education for more than two decades. She co-led the US team to the International Conference on Women in Physics in Birmingham UK in 2017. She is a Fellow of the American Physical Society, American Association for the Advancement of Science and American Association of Physics Teacher.
Thursday, August 20th, 4:00-5:00 pm, on Zoom
Prof. Plamen Atanassov (University of California, Irvine)
New Generation Electrocatalysts for Fuel Cells
Abstract: Platinum Group Metal-free (PGM-free) catalysts have been extensively developed for both Proton Exchange Membrane (PEM) and Alkaline Exchange Membrane (AEM) fuel cells aiming automotive, stationary and portable applications. In this lecture we will address the critical challenges that our team has faced on the way to practical application of such catalysts.
Over the last decade or so (while at the University of New Mexico), our team has developed the Sacrificial Support Method (SSM) as a main approach for the templated synthesis of hierarchically structured electrocatalysts materials. In this method the catalysts precursors are being absorbed on, impregnated within or mechanically mixed with the support (usually mono-dispersed or meso- structured structured silica), thermally processed (pyrolyzed) and then the silica support is removed by etching to live the open frame structure of a “self-supported” material that consists of the catalysts only.
This lecture will review the applications of this new class of electrocatalyst across several fuel cell applications: from automotive to microbial and from regenerative electrolyzer/ fuel cell units to water purification and desalination devices. These catalysts allowed also broad introduction of state-of-the art electrochemical technology in microbial electrochemical devices: microbial fuel cells, bio- electrochemical electrolyzers and advanced water treatment technologies. New/emerging directions for extending these materials types to catalysis of CO2 electro- reduction and N2 low temperature, low pressure electro-reduction aiming potentially at electrochemical ammonia synthesis will be discussed as well.
Bio:Plamen Atanassov graduated from the University of Sofia (1987) specializing in Chemical Physics & Theoretical Chemistry. He joined the Bulgarian Academy of Sciences (BAS) and become a Member of Technical Staff of its Central Laboratory of Electrochemical Power Sources (now the Institute for Electrochemistry & Power Systems). His initial work included materials solutions for metal-air batteries. He was a visiting scientist at the Frumkin’s Institute of Electrochemistry, Moscow, Russia studying bio-electrochemistry of enzymes and received a PhD in Physical Chemistry/ Electrochemistry from BAS.
Dr. Atanassov moved to the United States in 1992 and became a research faculty with the University of New Mexico (UNM). During the 90s he was involved in development of a several electrochemical biosensor technologies for biomedical, environmental, food safety and defense applications. In 1999 Plamen Atanassov joined Superior MicroPowders LLC (acquired later by Cabot Corp.), were he was a project leader in fuel cell electrocatalysts development and introduced spray pyrolysis for catalyst synthesis on industrial scale. He returned to UNM in 2000 as faculty member of the Chemical & Nuclear Engineering department. In 2007 Dr. Atanassov founded the UNM Center for Emerging Energy Technologies (CEET). From January 2012 to December 2013 Dr. Atanassov was the Associate Dean for Research of the UNM School of Engineering. July of 2015 Dr. Atanassov was promoted to a Distinguished Professor of Chemical & Biological Engineering and Chemistry & Chemical Biology. From January 2015 to September 2018 he served as director of the UNM Center for Micro-Engineered Materials (CMEM).
Starting October 2018 Dr. Atanassov joined University of California, Irvine where he is a Chancellor’s Professor with Henry Samueli School of Engineering, with the newly formed Department of Chemical & Biomolecular Engineering, holding secondary appointments with Materials Science & Engineering and with Chemistry. He is also affiliated with Los Alamos National Laboratory and is honorary professor of The Bulgarian Academy of Sciences. He served as a Vice-President of the International Society of Electrochemistry (2015-17). In 2018 he was inducted in the National Academy of Inventors. In 2019 Dr. Atanassov received ECS Energy Technology Division Award for his work on Platinum Group Metal-free (PGM-free) electrocatalysts. He is Fellow of both: The Electrochemical Society (2018) and the International Society of Electrochemistry (2020).
Dr. Atanassov materials for energy programs are focused on development of novel electrocatalysts: non-platinum electrocatalyst for fuel cells, nanostructured catalysts for oxidation of complex fuels, and new materials and technologies for energy conversion and storage. Dr. Atanassov bioelectrocatalysis programs range from enzyme electrochemistry, enzymatic and microbial fuel cells, and systems for biological and bio-inspired energy harvesting. Dr. Atanassov was the lead/principal investigator on DOD-AFOSR MURI and DOE-EPSCoR New Mexico Implementation Award. His research programs have been funded by DOE-EERE and DOD-ARO, NSF and Bill & Melinda Gates Foundation. He holds 50 issued US patents, substantial number of which have been licensed and are at the core of several catalyst products. He has published more than 400 peer-reviewed papers (bringing 26K+ citations and forming an h-index of 80), 20 chapters in books and edited a book on Enzymatic Fuel Cells. Atanassov serves on the editorial board of ACS Applied Energy Materials, ChemElectroChem (Wiley-VCH) and Electrocatalysis (Springer). He has served as an advisor for 35 completed PhD dissertations at UNM and had advised more than 20 postdoctoral fellows.
Spring 2020
Friday, March 13th, 11:30 am – 12:30 pm, Physical Science Rm. 321
Dr. David Cole (NAU)
The Quantum Thermodynamics of Black Holes
Abstract: As our community celebrates the life of Stephen Hawking, it is appropriate to consider the theories that initially brought his name into such prominence. Specifically, his work on the Quantum Thermodynamics of Black Holes will be discussed today. This discussion is quite startling for many different reasons. First, it is remarkable that the theoretical properties of such an exotic object can even be understood at all. Even more fascinating is that only a basic knowledge of introductory physics is required to understand many of the properties of black holes. We will naturally be led to the conclusion that black holes evaporate!
I had the honor of meeting Dr. Hawking about 27 years ago. I will begin the talk with a couple of anecdotes, and then we will derive a series of interesting “facts” about black holes.
Thursday, March 12th, 3:45-4:45 pm, SHB 502
Dr. Dale L. Huber (Sandia Nat’l. Lab./CINT )
Tuning Reaction Kinetics and Thermodynamics to Control the Magnetic Properties of Nanoparticles
Abstract: Traditional approaches to nanoparticle size control generally attempt to control size by controlling the nucleation step and varying the number of nuclei formed. I will present several approaches to nanoparticle size control and systematic variation that seeks to control and systematically vary nanoparticle size using identical nucleation events, but varying the nanoparticle growth. The approaches have in common the constant addition of nanoparticle precursor that leads to a steady state reaction, simplifying the kinetics of the nanoparticle formation reaction. This method, referred to as the Extended LaMer mechanism, leads to a linear increase in nanoparticle volume with time. The reaction can be extended for as long as the nanoparticles remain colloidally stable, allowing for systematic variation of nanoparticle sized through a wide range. The approach is general and can be applied to a range of synthetic systems to produce nanoparticles with exceptional reproducibility in size. One can also take advantage of the loss in colloidal stability to design a reaction that precipitates at a desired size. Since this loss of solubility is essentially a phase transition, the nanoparticle size is controlled by thermodynamics and not kinetics. This improves the ease of reproducibility of nanoparticle size with or without careful control of the reaction kinetics. A continuous reaction using this precipitation approach in magnetic nanoparticles will be discussed as will scale up and applications of these nanoparticles.
Bio: Dale L. Huber is a Distinguished Member of the Technical Staff at Sandia National Laboratories in the Center for Integrated Nanotechnology (CINT), a U.S. DOE Nanoscale Science Research Center jointly operated by Sandia and Los Alamos National Laboratories. He received a BA in Chemistry from the University of Pennsylvania in 1995 and a PhD in 2000 in Polymer Science from the University of Connecticut. He has been at Sandia since 2000, where his interests include novel approaches to the synthesis of nanomaterials, in particular polymeric monolayers, inorganic nanoparticles, and nanocomposites.
Thursday, February 27th, 3:45-4:45 pm, SHB 502
Prof. Stephen M. Goodnick (ASU)
Advanced Concept Photovoltaic Devices
Abstract: Nanostructured solar cells have multiple approaches by which they can improve photovoltaic performance through new physical approaches in order to reach thermodynamic limits of energy conversion, circumventing material limitations through band-gap engineered systems and providing new routes for low-cost fabrication by self-assembly or design of new materials. Here we focus on pathways to high efficiency solar cells and energy conversion using the various approaches employing nanostructured materials. We first discuss the limits of conventional photovoltaics, and advanced concept approaches to exceed the so-called Shockley-Queisser limit for single band-gap cells. We then discuss particular approaches that are being investigated including Si tandem solar cells, nanowire solar cells, and multi-exciton generation. Hot carrier solar cells are another approach to high efficiency, where phononic band-gap materials are being investigated to reduce energy loss. In particular, we discuss modeling and simulation efforts as part of the QESST Engineering Research Center on photovoltaics, with a focus on the role of ultrafast carrier/phonon dynamics in advanced concept systems.
Bio: Prof. Goodnick is currently the David and Darleen Ferry Professor of Electrical Engineering at Arizona State University. He received his Ph.D. degrees in electrical engineering from Colorado State University, Fort Collins, and was an Alexander von Humboldt Fellow in physics with the Technical University of Munich, Germany, and the University of Modena, Italy, from 1985 to 1986. He served as Chair and Professor of Electrical Engineering with Arizona State University, Tempe, from 1996 to 2005. He served as Associate Vice President for Research for Arizona State University from 2006-2008, and presently serves as Deputy Director of ASU LightWorks. He recently was a Hans Fischer Senior Fellow with the Institute for Advanced Studies at the Technical University of Munich (2013-2018). Professionally, he served as President (2012-2013) of the IEEE Nanotechnology Council, and served as President of IEEE Eta Kappa Nu Electrical and Computer Engineering Honor Society Board of Governors, 2011-2012. Some of his main research contributions include analysis of surface roughness at the Si/SiO2 interface, Monte Carlo simulation of ultrafast carrier relaxation in quantum confined systems, global modeling of high frequency and energy conversion devices, full-band simulation of semiconductor devices, transport in nanostructures, and fabrication and characterization of nanoscale semiconductor devices. He is a Fellow of IEEE for contributions to carrier transport fundamentals and semiconductor devices.
Thursday, February 20th, 3:30-4:30 pm, SHB 502
Prof. Bertrand Cambou (NAU)
Memristors: from the design of artificial neurons to cybersecurity
Abstract: Dr. Chua, 50 years ago, suggested that one important electromagnetic component was missing: the memristor. He provided an electromagnetic description of the component, without any experimental verification. About 40 years later, in 2008, physicists were able to fabricate the first memristors, in the form of arrays of cells. The electro-chemistry behind the implementation is the generation of cations in nanoscale electrolytes. Two important applications were proposed, the manufacturing of “universal” memories, and the design of artificial neurons for AI.
The purpose of the talk is to present an overview of the memristor technology, and to introduce the research work conducted at NAU to use memristors in cybersecurity. Memristors have the potential to enable the design of tamper resistant physical unclonable functions (PUFs). NAU partners such as the US Air Force, the Navy, Lockheed Martin, Sandia labs, and Crossbar technologies are interested by the potential to deploy such a technology to secure networks of IoTs. On the advanced research front, the design of keyless encrypting devices that operate like artificial neurons will be discussed.
Bio: Professor Cambou’s primary research interests are in cyber-security, and how to apply microelectronics to strengthen hardware security. This include the design of novel secure elements, Physically Unclonable Functions (PUF), True Random Generators (TRNG), and the usage of nanotechnologies such as ReRAM. He worked in the smartcard/secure microcontroller industry at Gemplus (now Gemalto), and in the POS/secure payment industry at Ingenico. He spent 15 years at Motorola Semiconductor (now NXP-Freescale) where he served in multiple capacities including CTO and was named “Distinguished Innovator” and scientific advisor of the BOD. In the last 5 years he worked as CEO in Silicon Valley in the high tech industry where his organization won a contract with IARPA with applications related to quantum cryptography. He is the author and co-author of 42 patents in microelectronics and cybersecurity.
Thursday, February 6th, 3:45-4:45 pm, SHB 502
Prof. Robert Whetten (NAU)
Forbidden Symmetries: Virus-like Clusters of Metal Atoms (& their Ligands) — Live NOW at NAU
Abstract: The Fundamental Discoveries in Materials Science rely on applying NEW (advanced) Methods & Instruments to OLD Materials, as much as the other way around. The question —‘Why [do we all] collaborate?’ — is answered largely by the urgently felt need for these Methods / Instruments — which explains why we devote so much effort to learning & acquiring them. In this Colloquium, we will present how:
- The capsid shells of most viruses have icosahedral symmetry. The arrangement of protein capsomers within the shell is identical to that of metal atoms (& their ligand head-groups) in highly stable clusters.
- The classification scheme used to characterize viral structures can be applied, with minimal change, to clusters of atoms and molecules.*
We’ll present the latest evidence (pro & con) re this statement, and a few of its implications, especially this : “A peculiar kind of (chiral) symmetry breaking, common to viruses but considered ‘unprecedented’ in the world of molecular & solid-state structure, will be demonstrated using visual & mechanical models (not to mention pure mathematics) of some historical & cultural significance.”
Abundant opportunities for further research in Applied Molecular Metallurgy arise from these methods & findings: They ‘Live NOW at NAU’.
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*This statement has been plagiarized (slightly modified) from the Abstract of T. P. Martin’s “VIRUS-LIKE CLUSTERS OF ATOMS”, Nobel Symposium 2001 volume pp. 1-11.
Bio: Prof. Whetten is Professor of Chemical Physics at NAU (APMS /¡MIRA!) since September 2019. Previously he was professor in the UTSA Physics & Astronomy (’12-’19), in the Physics & Chemistry Departments at GIT-Atlanta (’94 – ’12), and was Assistant (’85-’88), Associate (’88-’90), Full (’90-) Professor in UCLA’s Department of Chemistry & Biochemistry. He has co-authored ~ 250+ research articles that have attracted ~ 38,000 citations, a computed h-index of 89. He has supervised a dozen postdoctoral fellows and served as principal advisor to 25 PhD students, as well as many undergraduate researchers.
Thursday, January 30th, 3:30-4:30 pm, SHB 502
Prof. Károly Holczer (UCLA)
Potentials of diamond NV centers for quantum metrology
Abstract: Among the many defects identified in diamond, Nitrogen–Vacancy (NV(-)) centers are unique in that they have an intense, non-bleaching fluorescence sensitive to the ground state spin configuration. This enables Optically Detected Magnetic Resonance (ODMR) detection of the long coherence-time magnetic sublevels of isolated centers, leading to sensitive detection of local electromagnetic fields. An individual NV(-) site is able to measure/detect (sub)nanometer scale displacements of an elementary charge or a paramagnetic center. This displacement can possibly be induced by a conformation change of a nearby biological molecule. These exceptional properties make NV(-) centers the most promising atomic scale quantum metrology tool available at present.
Bio: Prof. Károly Holczer has been on the faculty of the UCLA Physics Department since 1993 and received his Ph.D. working with organic conductors in Budapest, Hungary. Prior to his appointment, he held multiple visiting positions in France (CEA Grenoble, CNRS Strasbourg, CEA Saclay) studying polymers and organic solids using NMR, EPR, Microwave impedance, and other techniques. From 1986 to 1989 he lead the development of the first (and only) commercial pulsed EPR spectrometer at Bruker (Germany), followed by visiting positions at UCLA and Orsay (France) studying organic, HTc, and Fullerene superconductors. At UCLA he contributed to the development of high-field EPR and scanning probe microscopy techniques and has been awarded DARPA contracts to develop sensors for single-spin (single-molecule) magnetic resonance. His interests include quantum information technology based on color centers in thin (carbon) diamond crystals.