Save the public calendar so you can track Colloquia events in your calendar of choice.
Zoom links can be accessed by clicking the title of the talks when they become available.
Meeting ID: 868 9925 6065
Join the Colloquium Mailing List
Don’t miss any events by signing up for our MIRA/APMS/NCI Mailing List!
Transmission electron microscopy can
be used to determine the crystalline structures
and compositions of solids at the micrometer to sub-nanometer scale. The visualization of structural irregularities in crystals has allowed observation of reaction pathways through transitions and reactions “frozen” before completion. Such information helped reconstruct nominally solid-state processes that previously could only be inferred. Early examples of studies of a range of minerals will show the development of the technique and its applications. Ongoing work is the use of TEMs to study minerals at high pressure. The talk will emphasize features close to the atomic scale but, through the study of unique carbon species, will extend to the largest known regions – the interstellar medium.
Over the past decade, single atom catalysis has evolved from being an academic curiosity to one of the most widely studied methods for the synthesis of novel catalytic materials. The promise of single atom catalysts is to lower the
requirements for platinum group metals by utilizing these metals more efficiently and to create novel catalytic pathways. For industrial applications, single atom catalysts need to be stable under reaction conditions and demonstrate durability during accelerated aging. Recent research shows pathways for scalable synthesis of single atom catalysts that might deliver catalysts meeting the thermal durability requirements of industry while yielding reactivity improvements over conventional supported metal nanoparticle catalysts. Since mobile single atoms constitute the dominant mechanism for catalyst sintering via Ostwald ripening, improving the stability of single atoms could help improve the durability of all heterogeneous catalysts used in industry. In this presentation we will describe recent work on an approach which we termed atom trapping. Our initial work focused on trapping volatile metal oxides such as PtO 2, to improve the durability of Pt catalysts, but we are now learning how this approach can be more broadly applicable. We will describe how fundamental understanding of the stabilization of single atoms and sub-nanometer particles and clusters can be helpful in applications ranging from emission control to hydrocarbon conversion.
n this presentation I will focus on the work done in areas related to
sustainable energy, water reclamation and remediation, biomedical devices,
and electrochemistry at microgravity. In the area of sustainable energy, our
lab has been working on the electrochemical synthesis of bulk catalyst
materials with low or non- precious metal content for fuel cell applications. Our
group has developed the Rotating Disk Slurry Electrodeposition (RoDSE)
technique for metal and bimetallic nanoparticle electrodeposition at high surface area carbon materials, such as Vulcan XC-72R. Galvanic displacement techniques have also been used to prepare Ag-Pd and Pt-M (M=Co, Cu, Ni) nanoparticle and nanowire catalyst in combination with RoDSE. These nanomaterials have been characterized for the oxygen reduction reaction (ORR) using the rotating ring disk electrode (RRDE) technique and Synchrotron Techniques such as operando X-ray absorption spectroscopy (XAS) and Extended X-ray Absorption Fine Structure (EXAFS). In the area of water reclamation and remediation, I will present our work on nano Zero Valent Iron (nZVI) nanoparticles for heavy metal sequestration and urease-P. Vulgaris for urea to ammonia conversion in urine purification bioreactor system. In the area of biomedical devices, our recent work on telomease activity sensing using gold interdigital electrodes and electrochemical impedance spectroscopy will be explained. Telomerase may be a cancer biomarker and a possible low-cost point-of-care cancer sensing device. Finally, I will present our autonomous electrochemical system for ammonia oxidation reaction studies, using platinum nanocubes, done at the International Space Station (ISS).
Dr. William “Buzz” Delinger taught for 48 years in the physics department at NAU. For this seminar, he will give a brief history of the department and tell of some of the important events that occurred during his tenure. He will also present some information about the people who established awards for NAU physics students. For the awards ceremony, the names of students who received the physics awards for 2022 will be read, and the students will be congratulated for their academic achievements
Abstract: Excited state interactions in spin-containing Donor-Acceptor and Donor-Bridge-Acceptor systems are important for understanding the impact of electronic coupling (Hab) on molecular electronics and how magnetic exchange interactions affect excited state processes. Our efforts have focused on determining excited state contributions to molecular bridge mediated electronic coupling, understanding how open-shell excited state singlet configurations promote long-range electron correlation, correlating magnetic exchange with molecular conductance, and developing new platforms for spin control of excited state dynamics in photoexcited donor-acceptor molecules. Using novel Donor-Bridge-Acceptor biradical and related complexes, we have been able to test recent theoretical hypotheses in molecular electronics as they relate to coherent superexchange in electron transfer/transport conduits, spin-polarized electron transport, and the control of quantum interference effects. Radical elaborated transition metal complexes represent ideal platforms for exploring the relationship between photoinduced charge separation and long-range spin correlation, impacting the solar energy, organic lighting, and molecular spintronics fields. These systems are also relevant to the emerging molecular quantum information science (QIS) field, allowing for the optical generation and manipulation of spin qubits. Here we will show how a combined spectroscopic and magentic approach, augmented by detailed bonding calculations, has provided keen insight into the electronic structure of these novel radical containing complexes in order to further our understanding of molecular electronic systems at the nanoscale.
The use of artificial intelligence for molecular design has been rapidly advancing. New generative models propose novel molecular structures to test, and deep learning can predict their molecular properties with high accuracy. The goal for these algorithms is optimizing a property by training against a large database of previously measured molecules. A major limitation is that these methods are not designed to be used concurrently with experiments and improving their accuracy as experimental data is gathered is non-trivial. Our research is focused on iterative molecular design where experiments are done concurrently instead of post-hoc in molecular design. This is accomplished by using maximum entropy biasing methods that can update predictive physics-based models with new experimental results.1 This improves predictive accuracy and ensures interpretable models.
Another challenge is the scarcity of data in molecular design. We are exploring with this with advances from few-shot learning, like meta-learning.2 Meta-learning translates experience from past related systems to new ones, minimizing the number of molecules necessary to train models. I will present results of these methods applied to peptides where we have studied a variety of tasks including antimicrobial, antifouling, and solubility predictions. Peptides are a model system because there is no ambiguity in encoding and generating them because they are linear biopolymers made of 20 amino acid monomers.
1. Experimentally Consistent Simulation of Aβ21–30 Peptides with a Minimal NMR Bias. DB Amirkulova, M Chakraborty, AD White – The Journal of Physical Chemistry B, 2020
2. Investigating Active Learning and Meta-Learning for Iterative Peptide Design. R Barrett, AD White – Journal of chemical information and modeling, 2021
3. Sequence, structure, and function of peptide self-assembled monolayers.
AK Nowinski, F Sun, AD White, AJ Keefe, S Jiang – Journal of the American Chemical Society, 2012.
Cryomineralogy, like mineralogy only cooler.
Australian Nuclear Science and Technology Organisation, Sydney, Australia
Ocean worlds have solid surfaces, and although water ice dominates many of these surfaces it material properties will be heavily influenced by the other chemical species it crystallises with. Moreover, studies of the minerals that form on these surfaces are clues as to what may lie below. Though we cannot yet reach these icy satellites and return a sample to Earth for investigation, we can recreate their simple compositions and extreme conditions in the laboratory. In contrast to terrestrial mineralogy, which has been subject to 100 years of laboratory measurements, we are only beginning to shed light on the range of materials that are formed on the ocean worlds.
Through laboratory studies cryominerals have been shown to be just as diverse as silicates in the structures and physical properties that they exhibit . From influence of sulfate on governing what water-rich hydrates form on Europa , to the plastic solids of methane and nitrogen that form on Pluto . A new and particularly rich area of discovery recently has been the variety of minerals that are likely to be formed on Saturn’s moon Titan  . This contribution will highlight recent developments in cryomineralogy, but also point to where much more laboratory work, and complementary modelling is needed.
1. Fortes, A.D. and M. Choukroun, Phase Behaviour of Ices and Hydrates. Space Science Reviews, 2010. 153(1-4): p. 185-218.
2. Maynard-Casely, H.E., et al., Mineral Diversity on Europa: Exploration of Phases Formed in the MgSO4–H2SO4–H2O Ternary. ACS Earth and Space Chemistry, 2021.
3. Maynard-Casely, H.E., J.R. Hester, and H.E.A. Brand, Re-examining the crystal structure behaviour of nitrogen and methane (in press). IUCrJ, 2020.
4. Maynard-Casely, H.E., et al., Prospects for mineralogy on Titan. American Mineralogist, 2018. 103(3): p. 343-349.
5. Cable, M.L., et al., Titan in a Test Tube: Organic Co-crystals and Implications for Titan Mineralogy. Accounts of Chemical Research, 2021: p. 4087-4094.
My research is directed to the development of optical instrumentation for biomedical measurements and addresses two broad topics: 1) Holography in tomographic imaging, and 2) Application of Raman spectroscopy in the life sciences.
Here, I will discuss our recent advances in building an incoherent detection arm for a Lattice Light-Sheet (LLS) microscope, called Incoherent Holography Lattice Light-Sheet (IHLLS). I will discuss development of this system including characterization of its performance and demonstrate a significant contrast improvement using both beads and neuronal structures within a biological test sample as well as quantitative phase imaging. The IHLLS has similar or better transverse and performance when compared to the LLS technique. In addition, the IHLLS allows for volume reconstruction from fewer z-galvo displacements, thus facilitating faster volume acquisition.
I have also worked on a technology that demonstrates the potential of Raman spectroscopy to determine with high accuracy the composition changes of the fatty acids and cholesterol found in the lipid droplets of prostate cancer cells treated with various fatty acids. The methodology uses a modified least-square fitting (LSF) routine that uses highly discriminatory wavenumbers between the fatty acids present in the sample using a new Support Vector Machine (SVM) algorithm.
The development of low temperature device technologies that have enabled flexible displays also present opportunities for flexible electronics and flexible integrated systems. In this presentation, we discuss fundamental materials properties including crystalline structure, interfacial reactions, doping, etc. defining performance and reliability of perovskite II-VI and oxide-based materials and devices for flexible and large area electronics. Materials characterization methods including RBS, XPS, XRD, etc. are used to analyze materials deposited by pulsed laser deposition, chemical bath deposition and inkjet printing. Finally, we demonstrate an integrated neutron / gamma ray sensor fully fabricated at UT-Dallas that includes wireless communication to a mobile device.
Abstract: Modern fluorescence labeling and optical microscopy approaches have made it possible to experimentally observe every stage of basic gene regulatory processes, even at the level of individual DNA, RNA, and protein molecules, in living cells, and within fluctuating environments. To complement these observations, the mechanisms and parameters of discrete stochastic models can be rigorously inferred to reproduce and quantitatively predict every step of the central dogma of molecular biology. As single-cell experiments and stochastic models become increasingly more complex and more powerful, the number of possibilities for their integrated application increases combinatorically, requiring efficient approaches for optimized experiment design. In this presentation, we will introduce two model-driven experimental design approaches: one based on detailed mechanistic simulations of optical experiments, and the other on a new formulation of Fisher Information for discrete stochastic process models. Using combinations of real biological experiments and realistic simulated data for single-gene transcription and single-RNA translation, we will demonstrate how experiment design approaches can be reformulated to account for non-gaussian noise within individual cells as well as for non-trivial measurement noise effects due to optical distortions and image processing errors.
Bio: Dr. Munsky received B.S. and M.S. degrees in Aerospace Engineering from the Pennsylvania State University in 2000 and 2002, respectively, and his Ph.D. in Mechanical Engineering from the University of California at Santa Barbara in 2008. Following his graduate studies, Dr. Munsky worked at the Los Alamos National Laboratory — as a Director’s Postdoctoral Fellow (2008-2010), as a Richard P. Feynman Distinguished Postdoctoral Fellow in Theory and Computing (2010-2013), and as a Staff Scientist (2013). He joined the Department of Chemical and Biological Engineering and the School of Biomedical Engineering as an Assistant Professor in January of 2014 and was promoted to Associate professor in 2020. He Dr. Munsky is best known for his discovery of Finite State Projection algorithm, which has enabled the efficient study of probability distribution dynamics for stochastic gene regulatory networks. Dr. Munsky’s research interests at CSU are in the integration of stochastic models with single-cell experiments to identify predictive models of gene regulatory systems and more complex biological systems, and his research is actively funded by the W M Keck Foundation, the NIGMS (MIRA), and the NSF (CAREER). Dr. Munsky is excited about the future the introduction of tools from physics and engineering into the quantitative study and modeling of biological processes, and he would love to talk about this with you!
High temperature molten salts were some of the first liquids to be studied in the 1960s and 1970s using the newly invented methods of molecular dynamics and Monte Carlo simulations. Simple salts such as 1:1 alkali halides were particularly attractive systems to model, given computational and algorithmic limitations of the time and the availability of experimental data against which computed properties are compared. Furthermore, there was a great deal of interest in understanding how charged fluids could be modeled computationally and whether both thermodynamic and transport properties could be captured using potentials that consisted of separate terms to treat long-range Coulombic interactions and shorter-ranged repulsion and dispersion interactions. Despite their importance in applications such as metal processing, heat transfer, and nuclear power, molten salt research fell out of favor, only to be replaced at the turn of the 21st century by low temperature “ionic liquids” – a new type of molten salt that was liquid at room temperature. Ionic liquids share many of the same properties as their high temperature cousins, but they also can have both polar and non-polar domains, giving them some unique solvation properties. Due to their low melting temperature, it is also much easier to study ionic liquids than molten salts.
In this talk, I will demonstrate how molecular simulations can help us understand how the thermophysical properties of high temperature molten salts and low temperature ionic liquids depend upon things such as structure, charge density, and composition. Motivated by applications such as battery electrolytes, solvents for gas separations, and safer nuclear energy generation, I will show how molecular simulations, machine learning, and advanced experimental characterization methods are helping us better understand these fascinating charged fluids.
ABSTRACT: Continued advancements in biomedical optical microscopy and fluorescent labeling techniques have enabled multi-dimensional visualization of biology in action at the single-molecule level. For example, multiple large-scale efforts are currently underway to create nanoscale spatial maps of thousands of individual RNA and protein species in millions of cells across all human organs. Many of the experiments across these efforts rely on multiplexed fluorescence molecular imaging. The quality and confidence of biological knowledge extracted from the resulting digital images depend on the molecular labeling strategy, the optical microscope’s design, and detector choices. Compromises are often necessary to achieve the required volume, imaging speed, number of molecules, samples, or other biologically driven experimental design criteria. Such compromises inevitably increase uncertainty when quantifying molecular identity and dynamics. I will discuss our recent efforts to reduce uncertainty in quantitative molecular imaging through improvements to the optical methods and computational tools used for high-speed, high-resolution, multiplexed, and volumetric fluorescence molecular imaging. Our efforts include a high numerical aperture oblique plane microscopy framework for 3D spatial transcriptomics in human tissue and a digital micromirror-based structured illumination microscopy framework for live-cell, sub-diffraction limited imaging.
Douglas Shepherd is an assistant professor in the Center for Biological Physics and the Department of Physics at Arizona State University. Prior to joining Arizona State University, he was an assistant professor in the Departments of Physics and Pharmacology at the University of Colorado Denver Anschutz Medical Campus from 2013-2019. He received his Ph.D. in Physics from Colorado State University and was a postdoctoral fellow at the Center for Integrated Nanotechnologies and Center for Nonlinear Studies at Los Alamos National Laboratory from 2011-2013. The focus of his research is developing quantitative imaging and statistical inference tools to build predictive models of genetic regulation in multi-cellular systems.
ABSTRACT: With the world facing a climate crisis due to increasing CO2 emissions, there is pressing need to develop and implement sustainable construction/engineering materials across the globe. Alkali-activated materials (AAMs) are one such sustainable alternative to conventional Portland cement concrete; yet questions remain regarding the long-term behavior of AAMs. Furthermore, for Portland cement, the use of extensive clinker substitution to reduce CO2 emissions has led to changes to the underlying chemistry of the main binder gel (calcium-silicate-hydrate, C-S-H, gel), where it is uncertain how these novel supplementary cementitious materials augment the long-term behavior (e.g., gel stability and pore structure) of the cement binder. In this talk, I will outline how fundamental materials science research is being used to address the long-term behavior unknowns of AAMs and certain Portland cement-based systems, where we are linking key experimental techniques with atomistic and larger length scale simulations. In particular, to assess gel stability in calcium-rich AAMs, we have used density functional theory (DFT), synchrotron-based X-ray pair distribution function (PDF) analysis and nuclear magnetic resonance (NMR) to investigate the influence of alkali and alumina incorporation on the structure and thermodynamics of C-S-H gel. The DFT results point toward a clear upper limit for sodium incorporation, beyond which the stability of the phase is compromised, while the experimental results show how alumina can be utilized to combat the destabilizing effects of sodium. We have also used DFT to uncover the early stage formation behavior of C-S-H gel and the influence of sodium and alumina, which has led to a tentatively proposed formation mechanism of the gel.
SPEAKER BIO: Claire White is an associate professor in the Department of Civil and Environmental Engineering and the Andlinger Center for Energy and the Environment, and is the acting associate director for research in the Andlinger Center for Energy and the Environment. She holds associated faculty status in the Departments of Chemical and Biological Engineering, and Mechanical and Aerospace Engineering, the Princeton Institute for the Science and Technology of Materials, High Meadows Environmental Institute, and Princeton Institute for Computational Science and Engineering. She completed her graduate studies in 2010 at the University of Melbourne supported by an Australian Postgraduate Award from the Australian government. After receiving her PhD, she worked as a postdoc at Los Alamos National Laboratory and was awarded a Director’s Postdoctoral Fellowship to research the atomic structure of low-CO2 alkali-activated materials. In 2013 she joined Princeton University.
White’s research focuses on understanding and optimizing engineering and environmental materials, including sustainable cements and materials for carbon capture, utilization and storage. One main thrust of her research portfolio entails the discovery and control of the chemical mechanisms responsible for formation and long-term degradation of low-CO2 cements and related systems. A second thrust is the development of new 2D materials for carbon capture with significantly reduced energy requirements for material regeneration. This research spans multiple length and time scales, utilizing advanced synchrotron and neutron-based experimental techniques, and includes the use and development of atomic and mesoscale simulation methodologies. Professor White is the recipient of a number of awards including an NSF CAREER Award, the RILEM Gustavo Colonnetti Medal, and the Howard B. Wentz Jr. Junior Faculty Award (Princeton University), and has been listed numerous times on the Princeton Engineering Commendation List for Outstanding Teaching.
Experimental studies in materials sciences, physics, chemistry, and biology often involve spectroscopy, diffraction, or microscopy. Typically, beams of photons or electrons probe the material, and many different techniques are available. Similarly, neutron scattering uses a diverse array of instruments that can resolve both structure and dynamics in a wide variety of materials. In this seminar, I will first provide a general introduction and overview and address the question when to use neutron scattering. Then I will present examples of my research on polymers, soft matter, and biology, to illustrate concepts and capabilities of neutron scattering in greater depth. The seminar intends to provide an opportunity for beginning conversations about the potential for use of neutron scattering in the research conducted by the Dept. of Applied Physics and Materials Science at Northern Arizona University.
The bottom row of the periodic table is famous for its radioactive elements, which compared to stable isotopes are little-explored. Many heavy radioisotopes have exotic nuclei which grant them enhanced discovery potential. Radioactive elements also hold promise for advancing technology. Modern atomic physics techniques, such as laser cooling and ion trapping, allow for efficient use of trace isotopes and their study in highly-controlled environments. In this context we will discuss our recent work with trapped and laser-cooled trapped radium ions. The radium ion holds promise for its use in an optical clock. The atom’s high mass makes it less sensitive to leading systematic uncertainties. The wavelengths needed for radium clock operation are in relatively photonic technology friendly parts of the spectrum, making it appealing to consider radium for realizing a robust and compact optical clock. In addition to its potential to advance timekeeping, the radium ion is also intriguing for synthesizing and controlling exotic radioactive molecules which could be used to sense new fundamental particles.
Laser fields tailored to interact with quantum systems on their natural, ultrafast time scales can provide an unprecedented degree of control over their dynamics. A longstanding dream has been to leverage these control capabilities towards high-value applications spanning physics, chemistry, materials science, and biology. However, the pursuit of these goals continues to be challenged by the prohibitive cost of quantum dynamics simulations, which are needed to support and inform quantum control advances in the laboratory.
Nevertheless, the future is bright. In this talk, I will discuss how quantum computing can alleviate these computational challenges and enable us to explore the principles and possibilities of quantum control in a scalable manner. To this end, I will introduce a hybrid quantum-classical algorithm that leverages quantum computing to facilitate simulation studies of quantum control. I will outline the associated costs, discuss different application areas, and consider the feasibility of its implementa- tion on quantum computing devices available today. Sandia National Labs is managed and operated by NTESS under DOE NNSA contract DENA0003525. SAND2022-2115 A.
When properly engineered, simple quantum systems such as harmonic oscillators or spins can be excellent detectors of feeble forces and fields. Following a general introduction to this fast growing area of research I will focus on using optomechanical systems as sensors of weak acceleration and strain fields. Ultralight dark matter coupling to standard model fieldsand particles would produce a coherent strain or acceleration signal in an elastic solid. I will discuss the feasibility of searching for this signal using various optomechanical systems. I will also show that current mechanical systems have the sensitivity to set new constraints on scalar field candidates for dark energy. Finally, I will briefly discuss the promise of quantum noise limited detectors in the search for beyond the standard model physics.
In the context of vacuum fluctuations, current and historic results in the measurements between Au-coated spheres of different radii and Au-coated plates will be presented. Special emphasis will be put in the effect of approximations used to calculate the interac- tion when the actual dielectric function of Au and geometry of the experiment are consid- ered. Residual effect due to electrostatic contributions will be discussed. Measurements with separations from 150 nm to over 8 microns between sphere and plate will be described.
These results will be used as a springboard to discuss our search for non-Newtonian gravity, where we have been able to impose the most stringent constraints for Compton wave- lengths between 40 and 8000 nm.
Time permitting, we will show current experiments going on in the lab to measure G and also to use a quantum detector to determine short range gravity.
Medical diagnostics have become increasingly distributed with the availability of point of care (clinic-based) and point of need (at home or in field) testing. Currently, high sensitivity diagnostics are limited to laboratories or point of care equipment the size of a refrigerator to small car. While handheld devices have made some inroads (e.g. self-monitoring blood glucose and pregnancy test), they are limited to applications with high analyte concentrations. Rapid, colorimetric tests have met the need for raid results with low infrastructure. Rapid flu, Zika, and even COVID colorimetric tests (color test strips) enable triage and help prevent transmission of infectious disease. However, they are generally considered non-quantitative or semi-quantitative at best.
Our work has focused on bridging the gap between the need for rapid results and highly sensitive, quantitative testing. With a focus on low resource settings, we have engineered a fluorescence-based testing system for point of need testing. This system has been demonstrated in India working with AIIMS (All India Institute of Medical Science) Delhi to address disproportionate mortality rates due to cervical cancer. As we were ramping up to a large clinical trial, the COVID-19 pandemic hit. We believed that our handheld, multiplexed, quantitative fluorescence-based system could be modified to enable RNA-based (gold standard) testing outside of a medical laboratory. Supported by the Arizona Department of Health Services, we navigated the hurdles of research in a pandemic. This presentation will cover the foundational technology and how we pivoted through the pandemic to enable point of need testing approaching diagnostic laboratory sensitivity.
Interactions between atoms and electromagnetic fields are at the core of nearly all quantum devices, with applications ranging from building quantum computers and networks, communicating quantum information over long distances, and developing quantum sensors of increasing precision. The miniaturization of these systems is critical to increasing their modularity as well as improving the efficacy of light-matter interactions by confining electromagnetic fields in small volumes. Thus atom-field interactions at nanoscales become a pivotal aspect of understanding and designing novel photonic devices.
In this talk, I will discuss two specific challenges relevant to nanoscale quantum optical systems and ways to engineer them: (1) Fluctuation phenomena—Forces, dissipation and decoherence induced by fluctuations of the electromagnetic field limit the control and coherence of quantum systems at nanoscales. I will present an overview of ways to engineer fluctuation phenomena in nanophotonic systems, and discuss specifically how collective effects can be used to tailor fluctuation-induced forces between atoms and surfaces. (2) Collective atom-field interactions over long distances—Distant correlated atoms coupled via waveguides can exhibit surprisingly rich non-Markovian dynamics arising from the memory effects of their intermediary electromagnetic environment. I will discuss how such a system demonstrates collective spontaneous emission rates exceeding those of Dicke superradiance (‘superduperradiance’), formation of macroscopically delocalized atom-photon bound states and limitations on long-distance quantum information protocols. These ideas pave way for building novel efficient light-matter interfaces and scalable quantum devices with long distance correlated quantum systems.
(ABSTRACT): From Prozac to perfume, sustainable plastics to solar energy, catalysis enables our current standard of living and controls our potential to progress sustainably. The reduced emissions of modern cars, the abundance of fresh food at our stores, the beginnings of green energy, and the new pharmaceuticals we use to treat disease are made possible by chemical reactions controlled by catalysts.
Research in my group has sought to design catalysts that can introduce and manipulate functional groups in both small and large organic molecules. These reactions encompass novel coupling processes(1) to facilitate the synthesis of medicinally important molecules, reactions that enable the introduction of fluorine and new fluoroalkyl substituents, and reactions that enable the introduction of functional groups into positions of molecules inaccessible by classical organic reactions.(2, 3) This lecture will introduce the importance of catalysis overall, some major challenges in the field, and ways that our group is seeking to address these challenges. Examples of important catalysts used today, and examples of strategies to discover and develop new classes of catalysts for future applications will be presented.
Kartik Srinivasan, National Institute of Standards and Technology and Joint Quantum Institute, NIST/University of Maryland
Nanophotonics provides the unprecedented opportunity to engineer nonlinear optical interactions through the nanometer-scale control of geometry provided by modern fabrication technology. In this talk, I will outline our laboratory’s efforts towards engineering nonlinear interactions to access a broad range of optical wavelengths, with a long-term goal of being able to develop methods and devices to access any optical wavelength of interest. I will focus on two specific device technologies, microresonator frequency combs and optical parametric oscillators, and discuss their development and potential application in areas such as optical atomic clocks. If time permits, I will also discuss how such nonlinear nanophotonic technologies can be used for the generation and transduction of quantum states of light.