Friederike Bock was awarded a Eugene P. Wigner Fellowship in 2019. Her fellowship research focused on producing very precise measurements of the photon signal in heavy ion and intermediate collision systems and on building a new detector that she hopes will unveil a new state of matter, gluonic matter, in currently uncharted phase space areas. Friederike’s mentor was Tom Cormier, who served as Relativistic Nuclear Physics group leader in the Physics Division during her fellowship.
Before becoming a Distinguished Staff Fellow, Friederike earned her PhD through a joint program of Lawrence Berkeley National Laboratory and the University of Heidelberg. Her project represented the first effort to look at direct photons in proton–proton and proton–lead collisions at the Large Hadron Collider at CERN, the European Organization for Nuclear Research, in Switzerland.
Christopher Bowland was awarded a Eugene P. Wigner fellowship in 2016. His fellowship research focused on building a multifunctional composites program to develop scalable routes to integrate nanomaterials into fiber-reinforced composites for embedded sensing applications. He has also been involved at ORNL with developing sustainable, 3D-printable polymers utilizing lignin and investigating the molecular structure of those polymers in different environments using neutron scattering at the Spallation Neutron Source and High Flux Isotope Reactor. Christopher’s mentor was Amit Naskar, who leads ORNL’s Carbon and Composites Group.
Christopher’s fellowship gave him the freedom and flexibility to develop multiple areas within the composites field in which he saw research opportunities for growth. His ongoing research interests include developing routes to integrate multifunctional composites into real-world structures. Christopher patented the technology developed during his fellowship, and he is partnering with a private company to commercialize multiple multifunctional composites. Christopher received his PhD in materials science and engineering from the University of Florida.
Christa Brelsford was awarded a Liane B. Russell fellowship in 2017. Her fellowship research focused on developing empirical and theoretical tools to increase our understanding of human–physical coupled systems, how they interact with and are influenced by the broader physical environment, and how collective social processes co-evolve with urban form. Her research was featured in a 2018 Science magazine video, and in 2020 she participated in ORNL’s Your Science in a Nutshell, an annual lightning-talks competition. In 2019 Christa won first prize in the Datathon on Computational Extremism at the International Conference on Computational Social Systems in Amsterdam. Working with a selection of YouTube channel comments, Christa and her team explored the temporal dynamics of online speech and how the discussion evolved with real-world events. Christa’s mentor was Budhu Bhaduri, Geospatial Science and Human Security Division Director.
Christa’s fellowship allowed her substantial flexibility to travel, meet people across many disciplines, and start to build interdisciplinary collaborations. She also focused during her fellowship on articulating a vision for a future research program that uses a broad range of quantitative methods and novel data sources to build a quantitative understanding of interactions between our social systems and the built environment. Christa joined the National Security Sciences Directorate as a research scientist after her fellowship. Christa earned her PhD at Arizona State University. Her dissertation research, which focused on urban water consumption, marked the first-ever comprehensive analysis of the water-conserving effects of one of the most widely used water conservation programs in the western United States.
Leah Broussard was awarded a Eugene P. Wigner Fellowship in 2016. Her research focused on developing new silicon detector technology for ultra-low noise and high resolution in detecting charged particles from free neutron beta decay. Also as a Fellow, Leah initiated a new program to search for mirror neutron oscillations using existing neutron scattering instruments at ORNL and pursued other areas of future growth for the Neutrons Group by characterizing detector effects and applying them to precision measurements in the beta decay of 45Ca and investigating the impact of the upcoming Second Target Station on fundamental physics. Leah’s mentor was David Radford, Fundamental Nuclear and Particle Physics section head in the Physics Division and a Corporate Fellow at ORNL.
Leah’s fellowship work has helped position ORNL as a world leader in fundamental neutron physics research. She was awarded a DOE Early Career Award in 2019. Her ongoing research interests include pursuing a better understanding of some of the most challenging experimental effects that can impact high-precision measurements in fundamental neutron physics and exploring a new line of research into the use of neutron scattering instruments for neutron oscillation searches. Leah received a PhD in physics from Duke University and was a Seaborg Postdoctoral Fellow at Los Alamos National Laboratory prior to joining ORNL.
Stylianos Chatzidakis was awarded an Alvin M. Weinberg fellowship in 2016. His research focused on developing new options for inspecting used nuclear fuel storage containers with cosmic-ray muon tomography. Stylianos produced the first research showing that muon momentum measurements could yield inspection images that are of higher quality and obtained in less time than was previously possible, resulting in reduced inspection costs and resources. He performed the first 3D neutron residual stress mapping of a spent fuel canister at ORNL’s High Flux Isotope Reactor neutron diffraction facility and is developing the MERF (Mobile Examination and Remediation Fixture) prototype, which will perform remote and automated remediation of spent nuclear fuel containers. His mentor was Josh Jarrell.
Stylianos’ fellowship provided him with a unique opportunity to work on a high-risk/high-reward research project that has kept him motivated to move his research area forward. He also cites as key benefits the guidance of senior ORNL staff and the credibility the fellowship has lent to his work and ability to identify new projects and funding. Since becoming a fellow, Stylianos was nominated as a Technical Point of Contact for DOE’s Nuclear Engineering University Program and as a member of the European Nuclear Safety Regulators Group’s Topical Peer Review Committee. His ongoing research interests include spent fuel inspection and remediation, muon tomography, aerosol transport, nuclear fuel simulations using GEANT4 and COBRA-SFS, and using advanced statistical pattern recognition and machine learning methodologies. Stylianos earned his PhD in nuclear engineering from Purdue University.
Kelly Chipps was awarded a Liane B. Russell fellowship in 2015. Her fellowship research focused on the nuclear reactions that power stars and stellar explosions. Kelly’s fellowship work stemmed from an effort with collaborators to build the world’s most dense gas jet target for stellar reaction studies. Her fellowship project goals included improving the operation of this target system and demonstrating that it could be successfully used for indirect reaction studies. Kelly also reanalyzed existing system data for new information and developed a neutron detector for complementary indirect reaction studies. Kelly’s mentors included Michael Smith, Nuclear Structure and Nuclear Astrophysical group leader in the Physics Division and Cheryl Bast, who was a team lead in the Biosciences Division during Kelly's Fellowship, and Ken Tobin, who was Measurement Science and Systems Engineering Division director during Kelly's fellowship.
Kelly’s fellowship gave her the opportunity to pursue unique lines of research, look back at existing data for new insights, and understand how the Laboratory operates. Her ongoing research interests include exploring the nuclear physics behind neutron star mergers such as the one observed by LIGO a few years ago, including the astrophysical r-process, which is thought to produce roughly half of the elements heavier than iron. Kelly earned her PhD in applied physics from the Colorado School of Mines.
Melissa Cregger was awarded a Liane B. Russell Fellowship in 2015. Her fellowship research examined how tree mortality altered belowground plant–microbe interactions and ecosystem carbon cycling. During this time, Melissa led development of multiple peer-reviewed journal articles highlighting the work of her team. Melissa’s mentor was Chris Schadt, senior scientist in the Biosciences Division.
Melissa’s fellowship gave her the freedom to explore new research directions while still engaging in collaborative work within ORNL. Interacting with other fellows also increased her awareness of the diverse research going on at ORNL and allowed her to grow her scientific network. Melissa joined the Biological and Environmental Systems Science Directorate as research staff after her fellowship. She was awarded a DOE Early Career Award in 2021. Her ongoing research interests include answering fundamental ecological questions in the field of plant–microbe interactions, with specific focus on understanding what variables drive shifts in these communities and how changes in plant–microbe interactions impact plant growth and health and alter ecosystem processes. She earned her PhD in Ecology and Evolutionary Biology from the University of Tennessee.
David Cullen was awarded an Alvin M. Weinberg Fellowship in 2010. His fellowship research focused on using recent advances in aberration-corrected scanning transmission electron microscopy (AC-STEM) and complementary analytical techniques to robustly characterize new catalysts for fuel cells. The capabilities and expertise developed under this fellowship led to many key contributions in correlating the atomic structure and chemistry of fuel cell materials with fuel cell durability and performance. David’s mentor was Karren More, Center for Nanophase Materials Science (CNMS) director.
The high visibility of David’s fellowship helped him establish collaborations with top fuel cell researchers in industry, academia, and other national laboratories. In turn, these collaborations provided additional mentors, accelerated scientific discovery, and opened new doors and opportunities. David was awarded the Presidential Early Career Award for Scientists and Engineers in 2019 and the Appalachian Regional Microscopy Society Young Investigator Award in 2013. His ongoing research interests involve correlating the atomic structure and chemistry of fuel cell materials with fuel cell durability and performance using advanced analytical AC-STEM. He has also developed a wide range of collaborations through the CNMS user program. David received his PhD in materials science and engineering from Arizona State University.
Omar Demerdash was awarded a Liane B. Russell fellowship in 2018. His fellowship research focused on generating improved machine learning–, physics-based computational methods that predict interactions of drugs and other small organic molecules with proteins and how drug binding modulates protein function. The primary science driver of the fellowship was cancer drug prediction, with the ultimate goal of predicting drugs with greater specificity and a lower side-effect profile. This work has applications to other human disease, including COVID-19, and the prediction of metabolite interactions implicated in plant–microbe interfaces, two areas in which Omar works. Omar’s mentor was Julie Mitchell, Biosciences Division director.
Omar’s fellowship has helped him become an independent researcher and understand how to integrate his skill sets and research interests into major ongoing ORNL research projects, including the neutron imaging and plant–microbe science focus areas. Additional ongoing research for ORNL exemplifies his approach of combining machine learning and physics and includes systematically improving potential energy models employed in molecular dynamics simulations of biomolecules using neutron scattering and other experimental data; developing models to predict the effect of mutations on structure and function; and predicting enzyme catalytic function. He received his PhD in biophysics and an MD from the University of Wisconsin–Madison, and subsequently received postdoctoral training in computational physical chemistry at the University of California–Berkeley.
Benjamin Doughty was awarded a Eugene P. Wigner fellowship in 2013. His fellowship focused on the development and use of nonlinear spectroscopy and microscopy methods. He developed new optical method and analysis routines for understanding chemistry at interfaces and in complex materials. Ben’s fellowship mentors included Bob Shaw, who led the Laser Spectroscopy and Chemical Microtechnology Group during Ben’s fellowship, and Phil Britt, who most recently served as Interim Associate Laboratory Director for the Physical Sciences Directorate.
Ben believes his fellowship gave him a good start to an independent scientific career. His ongoing research interests include understanding the molecular origins of chemical selectivity at interfaces, especially for chemical separations, using nonlinear optical methods to probe interfacial organization, orientation, and dynamics, and developing new tools to probe chemical localization and dynamics in complex living biosystems. Ben, now an R&D scientist in the Chemical Sciences Division, received a DOE Early Career Award in 2018. He received his PhD in physical chemistry from the University of California–Berkeley and held a postdoctoral position at Columbia University prior to joining ORNL.
Victor Fung was awarded a Eugene P. Wigner Fellowship in 2019. His fellowship research focused on obtaining fundamental physicochemical descriptors of chemical properties, conducting high-throughput materials screening and developing machine learning methods for materials discovery and design. Specific topics of Victor’s research included the capture and conversion of methane, heterogeneous C–H functionalization, and the structure/property prediction of nanomaterials. His mentor was Bobby Sumpter, Theory and Computation section head in the Center for Nanophase Materials Sciences (CNMS). Victor was based at CNMS’s Nanomaterials Theory Institute.
Before becoming a Distinguished Staff Fellow, Victor was a participant in the DOE Office of Science Graduate Student Research Program at ORNL. He went on to mentor students during his time as a Wigner fellow. Victor earned his PhD in chemistry from the University of California–Riverside.
Stephanie Galanie was awarded a Liane B. Russell Fellowship in 2018. Her fellowship research focused on facilitating enzyme and pathway discovery in the Populus (poplar tree) genus to increase drought tolerance and productivity, reduce recalcitrance, and manipulate metabolic profiles. By applying high-throughput heterologous microbial expression and mass spectrometry techniques to probe metabolism and help answer systems biology questions, her research improved our understanding of and increased our ability to enhance sustainability, robustness, and energy utility of organisms and ecosystems. Stephanie’s mentor was Tim Tschaplinksi, Biodesign and Systems Biology section head in the Biosciences Division.
Prior to her fellowship, she was a scientist at Codexis, a protein engineering biotechnology company. Stephanie is now Principal Scientist, Protein Engineering, with Merck & Co., Inc. She received her PhD in chemistry from Stanford University.
Chengyun Hua was awarded a Liane B. Russell fellowship in 2016. Her fellowship research focused on development of a predictive capability at ORNL for nanoscale thermal transport based on new ultrafast laser techniques and efficient Boltzmann transport simulations. Her research team successfully set up new ultrafast laser techniques in the Laser Spectroscopy Laboratory and provided a theoretical framework to understand nonlocal thermal transport in the nondiffusive regime. Chengyun’s mentors were Xin Sun, Interim Associate Laboratory Director, Biological and Environmental Systems Science Directorate; Lucas Lindsay, a condensed matter theorist in the Materials Science and Technology Division; and Jamie Morris, who led the Material Theory Group during her fellowship.
Chengyun’s fellowship allowed her to conduct independent research, broaden her scientific interests, and develop her professional network. Her current research as a staff scientist with the Energy and Transportation Science Division involves applying ultrafast laser techniques to a new target: emerging quasiparticles in quantum materials. Chengyun received her PhD in mechanical engineering from the California Institute of Technology.
Gang Seob “GS” Jung was awarded a Eugene P. Wigner Fellowship in 2019. His fellowship research focused on developing integrated multiscale models that enable predictive design and simulation of materials of interest at ORNL. His work included modeling the growth of 2D materials and their mechanics, carbon fiber processes at the atomic scale, and low-energy CO2 capture as well as developing multiscale computational modeling capabilities. GS’ mentor was Stephan Irle, Computational Chemistry and Nanomaterial group leader in the Computational Sciences and Engineering Division.
GS’ fellowship gave him the opportunity to collaborate with many scientists at ORNL and to work in various fields with various tools. His research interests include building a virtual lab where materials can be synthesized and characterized by combining and bridging advanced computational methods at different scales using ORNL’s world-leading high-performance computing resources. GS received his PhD in civil and environmental engineering from Massachusetts Institute of Technology.
Joseph Lukens was awarded a Eugene P. Wigner fellowship in 2015. During his fellowship, he conducted experimental photonics research in quantum information science. In 2016, Joe and colleague Pavel Lougovski discovered a new approach to quantum computing using frequency encoding, which was published in Optica in 2017. His mentors were Warren Grice, then group leader of ORNL’s Quantum Information Science Group, and Nicholas Peters, who now heads the Quantum Information Science Section.
Joe’s fellowship provided him with resources and freedom to pursue the most impactful research possible, which gave his career a jump start that he believes would be hard to find anywhere else. His ongoing research interests include quantum information processing with photons, Bayesian machine learning, quantum networking, and optical communications. Joe won the Significant Event Award in 2017 for ORNL’s first quantum technology license, Technology Commercialization Awards in 2017 and 2019, and a DOE Office of Science Early Career Award in 2019. His research was featured in the Optics and Photonics News “Year in Optics” in 2019. Joe earned his PhD in electrical engineering from Purdue University.
Petro Maksymovych was awarded a Eugene P. Wigner fellowship in 2007. His fellowship research focused on information materials at the intersection of phenomena of spontaneous polarization and electronic conductivity, contrasting the belief of their fundamental incompatibility. Topological defects were experimentally proven to allow coupling of polarization switching and conductivity, with prospects for highly energy efficient and continuously tunable neuromorphic computing elements for memory and computation. Petro’s fellowship work also led to new imaging tools for microscopy and dynamic spectroscopy of dipolar materials. Two key papers representing this work have been cited over 1,000 times to date. Petro’s fellowship mentors were Sergei Kalinin, a former Wigner Fellow who most recently served as Data Nanoanalytics group lead in the Center for Nanophase Materials Sciences (CNMS), and Arthur Baddorf, a research scientist with CNMS.
Petro believes that his fellowship allowed him to become both a technical expert and an independent thinker. He ventured into new research areas, connecting to fields previously unknown to him, and generalized his thought process away from specific cases. He says, even a decade later, many of his fellowship experiences continue to drive new ideas and scientific exploration. Petro’s ongoing research interests include developing methods to create and investigate hidden states of matter—long-lived structures and electronic properties that emerge from high-energy excitation or that exist entirely away from equilibrium—with particular focus on quantum and topological materials.
Petro, now a research scientist with CNMS, earned an ORNL Early Career Award for Individual Scientific Accomplishment and ORNL Director’s Award for Outstanding Accomplishment in Science and Technology, both in 2011. He was a Web of Science Group’s Highly Cited Researcher in 2019 and earned the Peter Mark Award from the American Vacuum Society in 2015 and the Martin and Beate Block Prize from the Aspen Center for Physics in 2010. Petro earned his PhD in chemistry from the University of Pittsburgh is 2007.
Michael McGuire was awarded a Eugene P. Wigner Fellowship in 2007. Research during his fellowship began in the field of thermoelectric materials but shifted to iron-based superconductors and related compounds. As part of the ORNL team working in this area, including fellow Wigner Fellow Athena Sefat, his work mainly involved the synthesis and characterization of these materials and focused particularly on their magnetic properties. This work established ORNL as a leader in this emerging and rapidly evolving field. Michael’s mentor was David Mandrus, who led the Correlated Electron Materials Group during his fellowship.
Michael was awarded a Gordon Battelle Prize in 2011 based on his fellowship research and was named a Highly Cited Researcher in 2014. His research has evolved over the years to include a variety of topics in magnetism. For his work in fundamental and applied aspects of magnetic materials, Michael has received an R&D 100 award and an Excellence in Technology Transfer Award from the Federal Laboratory Consortium, and he was recognized as a Highly Cited Researcher again in 2018 and 2019. He was elected a Fellow of the American Physical Society in 2017.
Michael’s current research efforts, situated at the interface of solid-state chemistry and physics, focus on developing layered magnetic materials that can be exfoliated into ultrathin and monolayer specimens for studying 2D magnetism and incorporated into van der Waals heterostructures, as well as magnetic topological materials and permanent magnets. He received his PhD in in physics from Cornell University in 2006.
Josh Michener was awarded a Eugene P. Wigner fellowship in 2015. His fellowship research focused on combining microfluidics and microbiology to influence how bacteria evolve. Josh’s mentors were Brian Davison, chief scientist in the Biosciences Division, and Kenneth Tobin, who was Measurement Science and Systems Division Director during Josh's fellowship.
Josh’s fellowship gave him the freedom to pursue independent lines of research and to respond as new research opportunities arose. Interacting with other fellows allowed him to build connections across disciplines and to learn about the wide array of research being conducted at ORNL. Josh, now a research staff member in the Biosciences Division, received a DOE Early Career award in 2019. He earned his PhD in bioengineering at the California Institute of Technology and held a postdoctoral appointment at Harvard University prior to his Wigner fellowship. Josh’s ongoing research interests include studying how enzymes and pathways function in different bacteria, with specific application to engineering bacteria for lignin valorization and enzyme discovery in nonmodel bacteria.
Jason Nattress was awarded an Alvin M. Weinberg fellowship in 2019. His fellowship research focused on developing a combined fast-neutron/gamma-ray radiography system that can distinguish between high‑Z materials and produce 3D tomographic images. His project provided useful new material identification/inspection techniques to improve scanning times for ocean-going cargo containers. He also has made significant contributions to several National Nuclear Security Administration–funded projects at ORNL, and the work in his project has led to additional funding for new projects. Jason is a member of the nEXO Collaboration, organized by Lawrence Livermore National Laboratory, for which he is the technical lead for the data acquisition system. He also serves on the editorial board for a new technical section of ORNL Review, a magazine that highlights research and development advances at the Laboratory. Jason’s mentor was Paul Hausladen, Advanced Radiation Detection, Imaging, Data Science, and Applications group leader and Distinguished Staff Scientist in the Physics Division.
Jason’s fellowship allowed him the flexibility to expand his research portfolio to include fundamental cross-section measurements of vital reactions of astrophysical, nuclear security, and societal importance. He joined the Physical Sciences Directorate as a research associate following his fellowship. Jason’s ongoing research interests include detection techniques for nuclear physics and nuclear energy and nonproliferation/security applications, specifically developing novel neutron detectors and neutron spectroscopy. He earned his PhD in nuclear engineering and radiological sciences from the University of Michigan in 2018.
Omer Onar was awarded an Alvin M. Weinberg Fellowship in 2010. His fellowship research focused on developing a power electronic interface for solar photovoltaic systems. During his fellowship, he contributed to an ARPA-E (Advanced Research Projects Agency–Energy) proposal, an experience that helped him learn to write effective proposals, resulting in his leading and winning many others. Omer’s mentor was Burak Ozpineci, Vehicle and Mobility Systems section head in the Building and Transportation Science Division.
Omer’s fellowship helped him quickly integrate into ORNL’s research culture and the national laboratory system. He also had great flexibility to get involved with projects in additional research areas. Serving as principal investigator on his fellowship project taught Omer to effectively manage research projects; plan a budget, milestones, and deliverables; and set metrics. Building on his project management experience, Omer now serves as PI on multiple projects per year, including DOE-funded research projects with industry partners and collaborators.
Omer’s ongoing research interests include transportation electrification applications of power electronics, with a primary focus on wireless power transfer systems for electric vehicle charging applications. He has received an R&D 100 award; ORNL Significant Event, Exceptional Effort, and Technology Commercialization awards; and best presentation and top journal reviewer awards. Omer earned a PhD in electrical and computer engineering from Illinois Institute of Technology.
Joe Paddison was awarded a Eugene P. Wigner Fellowship in 2019. His fellowship research focused on using neutron scattering techniques to develop a deeper understanding of the behavior of magnetic materials such as quantum-spin liquids. Joe explored materials for which the effects of quantum mechanics and crystalline geometry coincided to create new states of matter featuring entangled magnetic states. During his fellowship, he developed an approach to reveal more information from diffuse neutron scattering data, which was published in the December 2020 issue of the Physical Review Letters journal. As part of collaborative teams, he has since used this approach to understand important magnetic materials such as quantum-spin liquids and magnetic skyrmions. He is a Co-PI of the project, “Understanding Quantum Matter Beyond the Unit Cell” funded by the DOE Office of Basic Energy Sciences. Joe’s mentor was Andy Christianson, a neutron scattering scientist in the Materials Science and Technology Division.
Joe’s fellowship has given him the opportunity to develop and pursue new ideas while using the neutron-scattering facilities at ORNL. Joe was awarded the 2021 BTM Willis Prize by the UK Neutron Scattering Group in recognition of his contributions to the study of frustrated (i.e., disordered) magnetic materials using diffuse neutron scattering. His ongoing research interests lie at the intersection of neutron scattering, materials’ structure and characteristics, and models of materials’ behavior. Joe received a PhD in inorganic chemistry from the University of Oxford.
Chad Parish was awarded an Alvin M. Weinberg fellowship in 2009. His fellowship research focused on development of analytical electron microscopy for photovoltaics. Chad’s fellowship mentor was Karren More, Center for Nanophase Materials Science director.
Chad’s fellowship helped establish him as one of ORNL’s experts on using analytical electron microscopy to solve materials problems. His fellowship experience has allowed him to work on wide-ranging projects across different program offices and different energy-relevant fields over that last 10 years. His ongoing research interests include examining problems related to fission and fusion systems. Chad received a DOE Early Career Award in 2015, as well as the David J. Rose Award for Excellence in Fusion Engineering in 2018. He was elected to serve as secretary of the Microanalysis Society in 2018 and was reelected in 2020. He earned his PhD in materials science and engineering from North Carolina State University and was a postdoctoral fellow at Sandia National Laboratories before joining ORNL.
Christian Petrie was awarded an Alvin M. Weinberg fellowship in 2014. His fellowship research focused on incorporating advanced instrumentation, primarily fiber-optic sensors, into materials and fuels irradiation experiments. Chris’ current research focuses on nuclear fuel development and accelerated fuel qualification, including investigating additive manufacturing techniques for fabricating nuclear fuel components with embedded sensors and using accelerated, separate-effects tests to understand the effects of neutron irradiation on fuel performance and sensor operation. Chris’ mentors were Joel McDuffee, who was a senior research staff member during Chris’ fellowship, and Kurt Terrani, a former Weinberg Fellow who served as the technical director of ORNL’s Transformational Challenge Reactor program.
Chris’ fellowship allowed him to seed ideas for new sensor technologies that could be integrated into existing R&D programs focused on fuel performance and more general radiation effects on nuclear materials. He leads the WIRE-21 irradiation experiment, the most highly instrumented experiment ever performed in the High Flux Isotope Reactor; the experiment tests wireless sensors for monitoring nuclear fuel performance, fiber-optic sensors, and self-powered neutron detectors, among other sensors. He is now the Advanced Fuel Fabrication and Instrumentation group leader in ORNL’s Nuclear Energy and Fuel Cycle Division.
Chris has published over 100 peer-reviewed articles in journals and conference proceedings and has submitted 11 US patent applications primarily focused on advanced sensors for nuclear reactor applications, including fiber-optic–based sensors (e.g., temperature, pressure, strain, liquid level, and nuclear heating rates); methods for embedding sensors in metal or ceramic components; advanced postprocessing techniques for analyzing signals from fiber-optic sensors; and 3D-printed features on nuclear fuel cladding to enhance heat transfer and accommodate fuel swelling. Chris received the Landis Young Member Engineering Achievement Award from the American Nuclear Society in 2022 and earned his PhD in nuclear engineering from The Ohio State University.
Jacky Rios-Torres was awarded a Eugene P. Wigner fellowship in 2016. Her fellowship research focused on the development of control schemes for optimal coordination and operation of connected and automated vehicles (CAVs). She also analyzed the impact of CAVs on fuel consumption, safety, and mobility and the challenges inherent in the transition to full automation, including interactions between CAVs and human-driven vehicles. Her research has shown that fuel economy can be improved by 13–40% with CAV adoption. Jacky’s mentors have included Xin Sun, Interim Associate Laboratory Director, Biological and Environmental Systems Science Directorate; Robert Wagner, National Transportation Research Center director; and Paul Leiby, who leads the Energy Economic Analysis Team in the Energy and Environmental Sciences Directorate.
Being a Wigner Fellow has allowed Jacky to grow her professional network, develop cross-disciplinary research collaborations, and continue on the path of becoming a thought leader in her research area. She is now exploring ways to leverage ORNL capabilities in machine learning and high-performance computing to optimize CAV interactions with other traffic to achieve more efficient and safe mobility systems. Jacky earned her PhD in automotive engineering at Clemson University.
Katie Schuman was awarded a Liane B. Russell fellowship in 2015. In research focused on algorithms, programming, and usability of neuromorphic computing, Katie developed the Evolutionary Optimization for Neuromorphic Systems software framework and a training algorithm for building programs for neuromorphic computers. She also wrote a survey paper during her fellowship on the neuromorphic computing field. Katie’s mentor was Robert Patton, Learning Systems group leader in the Computer Science and Mathematics Division.
Her fellowship enabled Katie to help build the neuromorphic computing research area at ORNL. She also had the opportunity during her fellowship to focus on research that interested her and to build a base of work to support funding bids as she continues neuromorphic computing research at ORNL. Katie, who joined the Computing and Computational Sciences Directorate as a research scientist after her fellowship, received a DOE Early Career award in 2019. She earned a PhD in computer science from the University of Tennessee.
Athena Sefat was awarded a Eugene P. Wigner fellowship in 2007. Her fellowship research focused on developing iron-based arsenide superconductors. An article published during her fellowship, on which Athena served as the first author announcing the discovery of a new superconducting material, has been cited nearly 900 times to date. Her fellowship mentor was David Mandrus, who led the Correlated Electron Materials Group during Athena's fellowship.
Athena’s fellowship led to a DOE Early Career Award in 2010. As an ORNL senior scientist, she served as a scientific-technical advisor to the Experimental Condensed Matter Physics Program within DOE Basic Energy Sciences (DOE-BES). She also chaired ORNL’s Distinguished Staff Fellowship Committee (2016–2019), assisting with the selection of future Distinguished Staff Fellows at the lab. Athena now is DOE-BES Physical Behavior of Materials program manager. She earned her PhD in solid-state chemistry from McMaster University and was a postdoctoral fellow at Ames Laboratory prior to joining ORNL.
Kurt Terrani was awarded an Alvin M. Weinberg fellowship in 2010. His fellowship research addressed fundamental aspects of microencapsulated nuclear fuel fabrication and behavior. His mentor was Steven Zinkle, who is a Governor’s Chair in ORNL’s Fusion Energy Division.
The fellowship allowed Kurt to leverage capabilities across the laboratory including the one-of-a-kind nuclear reactor and hot-cell infrastructure to establish himself as the leading international expert in nuclear fuels with a focus on accident behavior and tolerance. He served as ORNL’s Transformational Challenge Reactor technical director before becoming Ultra Safe Nuclear Corporation’s director of USNC Core. He earned his PhD in nuclear engineering at University of California–Berkeley.
Singanallur Venkatakrishnan was awarded a Eugene P. Wigner fellowship in 2016. His fellowship research focused on developing algorithms for neutron computed tomography (CT) systems that draw on ideas from such diverse fields as statistical signal processing, image processing, inverse problems, and machine learning. Venkat used model-based image reconstruction approaches that combine statistical models for data and low-dimensional signal models for the underlying quantity to be measured to enable high quality neutron CT scans. His mentors included Hector Santos-Villalobos, Cyber Identity and Biometrics group leader in the Cyber Resilience and Intelligence Division; Philip Bingham, Energy Sensing, Analytics section head in the Electrification and Energy Infrastructure Division, and Ken Tobin, who was the Reactor and Nuclear Systems Division director during Venkat's fellowship.
Venkat’s fellowship gave him a great deal of freedom to pursue novel algorithms for a variety of imaging applications. It also allowed him to connect with scientists in different divisions at ORNL, leading to fruitful collaborations. While a Fellow, Venkat became an IEEE Senior Member and an elected member of the IEEE Signal Processing Society’s Technical Committee on Computational Imaging, his core area of research. His ongoing research interests include computational imaging and inverse problems. Venkat is particularly interested in using machine learning methods to improve the capability and quality of 3D-imaging instruments being employed across domains at ORNL, including electron microscopes, x-ray micro-CT scanners, ultrasound systems, and neutron CT scanners. He received a PhD in electrical and computer engineering from Purdue University.
Zac Ward was awarded a Eugene P. Wigner fellowship in 2009. His fellowship research focused on developing novel experimental approaches to interrogate the physics of strongly correlated electron systems. That work led to the observation of isolated metastable electronic-phase domains, which gave access to previously hidden information on the physics driving correlated phase dynamics.
Zac’s fellowship helped establish him as an ORNL expert in thin film correlated materials design and synthesis. He was awarded a DOE Early Career Award in 2017 for his efforts related to designing metastability in strongly correlated systems. Zac has performed organizing and elected roles in several professional societies and currently serves on the Journal of Applied Physics Editorial Advisory Board. He enjoys volunteering in science outreach programs such as ORNL’s traveling Science Fair and the Appalachian Regional Commission/ORNL Summer Science Institute.
Zac’s ongoing research interests include developing new methods of controlling individual order parameters to probe the physics driving quantum and energy-related functionalities in new materials. He pioneered the development of low-energy noble ion implantation as a means of strain-doping complex materials to tune orbital degeneracies and lattice symmetry. He is currently working to understand how disorder between local quantum states can lead to macroscopic magnetic, charge, and orbital ordering in crystalline materials. Zac earned his PhD in physics from the University of Tennessee.
Travis Williams was awarded a Eugene P. Wigner fellowship in 2013. His research focused on performing neutron scattering research on magnetic materials. He investigated the permanent ferromagnet MnBi, which is of interest as a less costly replacement for rare-earth permanent magnets for room-temperature applications. Travis was able to show how atomic-scale interactions contribute to the magnet’s strength. Mark Lumsden, Spectroscopy section head in the Neutron Scattering Division, was Travis’s mentor.
Travis counts among his fellowship’s many benefits the opportunity to work on cross-disciplinary projects and the ability to pursue collaborations and explore novel research techniques. His current research as a staff scientist with the Neutron Sciences Directorate focuses on using neutron scattering and other experimental techniques to understand magnetism in 4f and 5f systems. Travis received a PhD in physics from McMaster University.
Guannan Zhang was awarded an Alston S. Householder Fellowship in 2012. His fellowship research focused on stochastic approximation and uncertainty quantification. He developed several stochastic approximation algorithms that have significantly accelerated high-fidelity particle simulators used in studying the stability of magnetically confined plasmas in nuclear fusion reactors. Guannan’s mentor was Rick Archibald, Data Analysis and Machine Learning group leader in the Computer Science and Mathematics Division.
Guannan’s fellowship provided him with sufficient flexibility to explore new research areas, which played an important role in his research career development. He was awarded a DOE Early Career Award in 2022. His ongoing research interests include artificial intelligence and scientific machine learning. Guannan joined the Computing and Computational Sciences Directorate as a computational mathematician after his fellowship. He earned his PhD in applied mathematics and computational science from Florida State University.