Luke Bertels, a Eugene P. Wigner Fellow, earned his PhD from University of California–Berkeley. His dissertation focused on theoretical chemistry with a specialization in molecular electronic structure theory. His work explored the role of zeroth-order representations for correlated wavefunction calculations. Luke’s mentor is Ryan Bennink, Quantum Computational Science group leader in the Computational Sciences and Engineering Division.
Luke will focus his fellowship research on the development of adaptive classical and quantum machine learning approaches for studying quantum chemistry. The work will provide new, efficient methods to extend the reach of both classical and quantum simulation towards the study of strongly correlated molecules. His ongoing research interests include quantum algorithms for physical simulation and electronic structure theory of molecules and materials.
KC Cushman, a Liane B. Russell Fellow, earned her PhD from Brown University. Her dissertation explored the use of novel remote-sensing tools for measuring 3D structure and carbon dynamics in forests. KC's work demonstrated the value of drone technology for complementing traditional field- and satellite-based measurements of forests. Using drones for targeted, landscape-scale data collection allowed her to demonstrate that optical satellite data may underestimate tropical forest disturbance frequency and to explore how new estimates of forest biomass from spaceborne lidar (light detection and ranging) can be made robust to seasonal patterns of leaf production. KC’s mentor is Anthony Walker, Ecosystems Processes group leader in the Environmental Sciences Division.
Working in the Ecosystems Processes Group in the Environmental Sciences Division, KC will leverage ground observations, near-surface remote-sensing data, and satellite platforms to develop innovative approaches to study ecosystems across spatial and temporal scales. Her work will explore the use of emerging SAR (synthetic aperture radar) data to study ecosystem structure. Results from this project will allow scientists to better monitor, understand, and predict the effects of disturbances on natural systems.
KC’s research interests include studying variation in forest structure and function across space and time; understanding and predicting global cycles of carbon, water, and nutrients through forest science; and combining remote-sensing measurements and field-based observations to understand how organismal mechanisms affect landscape-scale processes.
Jeff Foster, an Alvin M. Weinberg Fellow, earned his PhD from Virginia Tech. His dissertation focused on developing a methodology to leverage gaseotransmitters, specifically hydrogen sulfide, for human therapy. His work showed that hydrogen sulfide exhibits selective anticancer activity and may represent a promising alternative cancer therapy. Jeff’s mentor is Tomonori Saito, a chemist in the Chemical Sciences Division.
Jeff will focus his fellowship research on developing homogeneous, stimuli-responsive catalysts for precision polymer synthesis. His methodology will enable kinetic control over polymer sequence, providing a tool to create polymers with intentionally designed sequences. Fundamental sequence–structure–property relationships discovered during Jeff’s fellowship work will provide a framework for the design of future sustainable materials for packaging, construction, energy storage, and medicine. His ongoing research interests leverage a framework of synthetic methodology, homogeneous catalysis, and organic material science to uncover structure–property relationships, create novel materials with emergent functionality, and develop efficient and sustainable manufacturing processes.
Brenden Ortiz, a Eugene P. Wigner Fellow, earned his PhD in material science from the Colorado School of Mines in 2019. His dissertation focused on accelerating the discovery and optimization of thermoelectric materials by developing techniques that aimed to accelerate both the theoretical and experimental aspects of material science. Brenden’s work resulted in the discovery of a new family of metals, AV3Sb5 (A: K, Rb, Cs) materials, which show a unique new quasi-2D kagome lattice and exhibit superconductivity, a charge density wave, and potential nontrivial topology. The combination of these properties together on the kagome lattice had never been seen before. His study renewed interest in the examination of kagome metals by researchers around the world, with over 350 additional manuscripts being published on this family in the past 2 years. Brenden’s mentors are Michael McGuire, Correlated Electron Materials group leader, and R&D staff member Andrew May, both in the Materials Science and Technology Division.
Brenden will focus his fellowship research on developing methods to control and predict the emergence of electronic instabilities in correlated metals. His project will facilitate the design of the next generation of quantum materials through a better understanding of the connection between the electronic structure of materials, the high-dimensional chemical space, and the emergence of correlated electron properties, such as superconductivity and charge density waves. Brenden’s ongoing research interests include the connection between chemistry and thermodynamics in complex materials. He is also interested in high-dimensional chemical spaces and how the influence over alloys, dopants, and defects can radically alter material properties.
Yue Yuan, an Alvin M. Weinberg Fellow, earned her PhD in fiber and polymer science and a graduate minor in biochemistry in 2021 from North Carolina State University. Her dissertation focused on the challenges existing in global management of carbon dioxide emissions and recent research on applying biocatalysts, as an alternative to high-energy and high-cost traditional liquid solvents in carbon dioxide scrubbing processes. Her work introduced a new category of material that has hierarchical structure and biocatalytic function. Her study also uncovered the mechanism of enhanced catalyzed reactions at liquid–gas–solid interfaces. Yue Yuan’s mentor is Dr. Rigoberto Advincula, Macromolecular Nanomaterials Group Leader at the Center for Nanophase Materials Sciences.
Yue Yuan will focus her fellowship research on renewable macromolecular nanomaterials, particularly how their charge and hydrophobicity impact their reassembly with additive manufacturing techniques, outside the biological system. Her ongoing research interests include working on advanced functional materials, particularly bioderived and bioinspired materials, and focusing on bridging fundamental bioscience discoveries with advanced materials manufacturing through revealing the mechanisms behind the phenomena we observed in material formation.
Marm Dixit, an Alvin M. Weinberg Fellow, earned his PhD from Vanderbilt University. His dissertation focused on investigating processing–structure–function relationships in solid-state batteries. Marm’s thesis provided insight into failure mechanisms for several prevalent material alternatives of solid electrolyte as well as design rationales for achieving improved performance of solid-state batteries. These pivotal material technologies will enable electrification of the transportation sector and provide affordable, high energy density (HED), durable, and safe energy storage. Marm’s mentor is Ilias Belharouak, Electrification and Energy Infrastructure section head in the Electrification and Energy Infrastructure Division.
Marm will focus his fellowship research on evaluating and understanding the fundamental behavior of novel solid electrolyte materials against metallic anodes and high-voltage cathodes to generate insights that can be leveraged into high-performance devices. He will also investigate the influence of component fabrication routes, device integration steps, and operation protocols on device performance to provide energy storage solutions with techno-economic feasibility. His project is expected to enable scalable production of HED solid-state batteries that significantly impact the mobility industry and help in the electrification of the sector. In fall 2021, Marm was awarded a Toyota Young Investigator Fellowship for Projects in Green Energy Technology from the Electrochemical Society. The fellowship provides funding for young scientists and engineers to pursue battery and fuel cell research with an emphasis on unique, innovative, or unconventional technical approaches and the feasibility of the technology to positively impact the field of green energy. His ongoing research interests include energy storage and conversion, electrochemistry, synchrotron/neutron science, imaging, heterogeneous catalysis, and big data and machine learning.
Addis Fuhr, an Alvin M. Weinberg Fellow, earned his PhD from the University of California–Los Angeles. His dissertation focused on elucidating the electronic, optical, and magnetic properties of defects in quantum dots, and theory–experiment matching. Ternary copper-based quantum dots have unusual physical properties, making it difficult to determine how to optimize them for different applications. He helped unravel the mysterious origins of their unusual electronic, optical, and magnetic properties by combining theory with experiment to reveal mechanisms for defect formation and corresponding physics. His research helped improve the performance of CuxIn2-xSeyS2-y quantum dots for applications such as solar windows, solar cells, field-effect transistors, and light-emitting diodes. Addis’s mentor is Bobby Sumpter, ORNL Corporate Fellow and Theory and Computation section head in the Center for Nanophase Materials Sciences.
Addis is researching ways to integrate machine learning with ab initio computational chemistry and experimental materials characterization methods to enrich our understanding of the chemistry and physics of heterogeneity and defects in materials and to accelerate the discovery of materials with specific, desired functionality. His project is expected to enable accelerated discovery and understanding of the physics and chemistry of defects and heterogeneity in complex materials for applications such as multiferroics, quantum materials, solar energy, and battery, refractory, or nuclear materials. Addis’s ongoing research interests include combining theory with experiment to understand structure–property relationships for defects, heterogeneity, and coexisting phases in materials. He also is interested broadly in using theory/artificial intelligence to predict experimental signatures, and aiding in the design of materials with target functionalities.
Jake Nichols, an Alvin M. Weinberg Fellow, earned his PhD from Princeton University. His dissertation focused on modeling the erosion, transport, and redeposition of wall materials in magnetic fusion devices that utilize multiple materials for plasma-facing components and examining how these materials temporally evolve into mixed-material surfaces. His thesis clarified the mechanisms that limit the lifetime of thin film–conditioning techniques that are frequently applied to the walls of magnetic fusion devices to control impurities. This understanding will allow for more targeted conditioning of the wall surfaces, enabling present fusion devices to operate at higher performance for a longer period of time between maintenance phases. Jake’s mentor is Zeke Unterberg, Power Exhaust and Particle Control group leader in the Fusion Energy Division.
Jake will focus his fellowship research on developing novel models for filamentary plasma transport in the edge of magnetic fusion devices that incorporate advanced divertor regimes and realistic 3D wall geometries, helping to constrain estimates of the heat and particle fluxes that will strike different parts of the vessel wall in a pilot plant–scale fusion device. His project is expected to advance optimization of the main wall of a fusion reactor by shaping the wall geometry such that the strongest fluxes are concentrated on components designed for the task. This approach will improve component reliability while reducing overall reactor cost. Jake’s ongoing research interests include plasma–material interactions, tokamak edge and divertor plasma physics, and integrated modeling of fusion systems.
Alice Perrin, an Alvin M. Weinberg Fellow, earned her PhD from Carnegie Mellon University. Her dissertation focused on the characterization of high-entropy alloys for magnetocaloric applications. Alice developed the first high-entropy alloy studied for magnetocaloric properties and demonstrated that the distribution of magnetic exchange interactions caused by the spread of dissimilar atoms on a single lattice favorably broadened the magnetocaloric response. Alice’s mentor is Ying Yang, a research scientist in the Microstructural Evolution Modeling group in the Materials Science and Technology Division.
Alice will focus her fellowship research on studying the effects of irradiation on grain boundary segregating nanocrystalline alloys; typically, solute segregation in nuclear materials reduces ductility and leads to embrittlement, but materials stabilized by high segregation energies that lead to equilibrium microstructures in which solutes decorate grain boundaries by design have not been studied for radiation tolerance. The small, thermodynamically stabilized nanocrystalline grain size of these alloys should increase their radiation tolerance due to the large area of grain boundaries that act as defect sinks. Her work will focus on understanding the segregated solutes’ behavior under irradiation and the resulting changes in microstructure and grain size, phase stability, and radiation hardening in this class of alloys. This research will potentially open up a new avenue of radiation-tolerant alloy design that takes advantage of new types of microstructures that utilize solute segregation as a feature instead of a bug. Alice’s ongoing research interests include nonequilibrium processing, thermodynamic and kinetic stabilization of metallic microstructures, functional alloy design for radiation resistance, and electrical and magnetic properties; additive manufacturing; and high-entropy alloys.
Logan Sturm, an Alvin M. Weinberg Fellow, earned his PhD from Virginia Tech. His dissertation focused on cyber-physical security for additive manufacturing systems. Logan’s thesis provided a framework for identifying and mitigating sabotage attacks on additively manufactured parts using in situ monitoring, new techniques for securely transmitting part quality information to air-gapped side-channel monitoring systems, and an impedance-based method of nondestructively evaluating additively manufactured parts for defects. Logan’s mentor is Mason Rice, Resilient Complex Systems section head in the Cyber Resilience and Intelligence Division.
Logan will focus his fellowship research on identifying cybersecurity vulnerabilities in additive manufacturing systems and developing techniques and platforms to mitigate the vulnerabilities. His work will include evaluating in‑process monitoring systems for metal laser powder bed fusion in an adversarial setting, developing new methods for improving the robustness of these systems to attacks, and investigating human factors and training to improve awareness and understanding of cybersecurity threats in manufacturing. Logan’s project is expected to provide improved security for manufacturing systems and increased awareness of the threats facing modern digital manufacturing. Logan’s ongoing research interests include in situ monitoring for additive manufacturing systems, vulnerability assessment in advanced manufacturing, data analytics for malicious defect detection, secure distributed manufacturing, unclonable security features for anticounterfeiting, and human–machine interactions in a cybersecurity context.