Katharine B. Gebbie Young Scientist Award
The Sigma Xi Katharine B. Gebbie Young Investigator Award honors early career researchers at NIST. These researchers are invited to give seminars on their work as part of the recognition. Abstracts are included below, where available.
Awardees include:
2023
Dr. Alexander Grutter, NIST Center for Neutron Research
Lost in reciprocal space: Metrology for Futre Quantum Material Device Platforms
As our ability to speed up and shrink down microelectronics fades, there is a race to build devices which operate in fundamentally differently ways from traditional Silicon-based electronics. Whether for ultra-low power nonvolatile memory or fault tolerant quantum computers, these devices are typically based on thin films of new materials supporting exotic physics. Precision metrology of these new material platforms, especially at surfaces at interfaces, is critical to understanding their behavior and unlocking new applications. In this talk, I will describe how we employ neutron reflectometry to provide a sub-Ångstrom resolution picture of thin film structures. Using the unique sensitivity of the neutron, we can watch hydrogen move or detect a single atomic monolayer of magnetized atoms, revealing the physics which can support a new generation of quantum material devices.
2022
Dr. ALBERT RIGOSI, quantum measurement Division, PML, NIST
using the quantum hall effect in graphene for defining the ohm
Did you know that the United States recently became the first nation to use graphene in how the unit of the ohm is defined? Monolayer epitaxial graphene has been shown to have clearly superior properties for the improvement of devices whose function depend on the quantum Hall effect and serve a critical role in defining electrical units for US industries. Recent progress in device development will be summarized, including: (1) Stabilizing and controlling graphene’s electron density over centimeter scales to ensure viable commercialization. (2) Expanding the utility of these graphene-based devices by creating arrays that use superconducting electrical contacts. (3) Exploring p-n junctions as a possible future device to access many different quantum Hall resistance values.
2018
Dr. David Long, Chemical Sciences Division, MML, NIST
Optical spectroscopy: frequency combs, radiocarbon, microcavities, and satellites
The work of myself and my collaborators has focused upon the application of novel highly sensitive spectroscopic techniques to present problems in atmospheric chemistry, atomic physics, and metrology. We have developed a wide range of cavity-enhanced instruments in which an optical cavity (i.e., a pair of highly reflective mirrors to form a resonator) serves to dramatically increase the instrument’s sensitivity by allowing for tens or even hundreds of thousands of transits through the absorbing medium. This has enabled spectroscopic measurements of radiocarbon (14C) for application areas such as dating and source apportionment. In addition, this instrumentation has allowed for the production of reference data to support atmospheric remote sensing by satellites. Further, we have developed approaches for the generation of optical frequency combs which allow for multiplexed, single-shot measurements of atomic and molecular gases. Finally, we have begun to apply these methods to the development of sensors based upon optical microcavities which offer exquisite sensitivity to external perturbations.
2016
Dr. Stephen Jordan, NIST Information Technology Laboratory
Dr. Nicholas Butch, NIST Center for Neutron Research
The Allure of Hidden Order
Among the unsolved mysteries of condensed matter physics, perhaps that most provocative is that of Hidden Order, an electronic phase that emerges at low temperatures in the intermetallic compound URu2Si2. Over the course of thirty years, many hundreds of publications have been devoted to its resolution, yet today experts still do not agree on what precisely is going on. In this talk, I will describe how interactions between bound and itinerant electrons lead to weird effects in crystals, and how such emergent behavior can serve as a platform for exotic physics. Along the way, I will highlight how neutron scattering measurements have helped us to better understand this enigma, and what we think may still be hiding.
2015
Dr. Chandler Becker, MML Office of Data and Informatics and Materials Science and Engineering Division, MML, NIST
How can we find and use materials data to support our materials science?
One of the outcomes of the Materials Genome and other similar initiatives is an increase in the amount of materials science data now being generated and distributed. Even more is on the way. But how does a researcher find data or make data useful to someone else? How does one know where to look, judge the quality of the data, or decide whether it is applicable? This seminar will address several approaches to addressing these questions, including the development of a materials resource registry system to make finding materials data easier and work to facilitate the industrial use of molecular simulations of metallic materials. It will also describe efforts to look across the boundaries between research disciplines to find applicable analysis approaches while recognizing that each research problem is unique.
2014
Dr. Yun Liu, nIST Center for Neutron research
Dr. R. Joseph Kline, Materials Science and Engineering Division, MML, NIST
Visualizing Nanostructures with X-Rays
The semiconductor industry has revolutionized our way of life. It is hard to imagine life without all of our electronic gadgets. These electronics are made possible by tremendous technological advances in semiconductor manufacturing. The semiconductor industry has continuously shrunk the size of their transistors and memory cells for over 40 years following what is known as Moore’s Law. The devices have gone from macroscopic transistors nearly 1 mm in size to nanoelectronics under 20 nm in size. The latest generation of computer microprocessors have a minimum feature size of 14 nm, or about 30 silicon atoms across. This extreme scaling results in large increases in performance and power efficiency while decreasing the cost per transistor. In the near future, the industry will be manufacturing less than 10 nm features. These small features challenge the physical limits of current metrology tools. I will discuss the development of a new X-ray based measurement method with the potential to provide the needed resolution of the dimensions and shape of next generation semiconductor nanostructures. I will show examples of a series of nanostructures not possible to measure by other means.