Simple Molecular Systems at Ultrahigh Pressures

Non-Technical Abstract: Subjecting materials to high pressures can create exotic materials and unveil intriguing physical phenomena that are not readily accessible under normal conditions. This project studies new materials with unprecedented properties formed from simple molecules such as hydrogen, methane, oxygen, water, when subjected to pressures from near ambient conditions to many millions of atmospheres, in combination with variable temperatures and magnetic fields. In particular, the project focuses on hydrogen-rich materials that can transport electrical current without resistance at and possibly above room temperature under pressure. This project advances the study of this very high-temperature superconductivity with the discovery, characterization, and synthesis of new materials that exhibit this behavior, including at lower pressures near ambient conditions. The results could lead to new practical superconductors and related materials for energy and quantum applications. New techniques are developed in-house and at national user facilities that are made available to the broader scientific community. Both graduate and undergraduate students are trained in the latest research methods for the study of matter and materials under extreme conditions at the University of Illinois Chicago and its partner institutions, including national laboratories. Technical Abstract: This project investigates fundamental interactions and emergent behavior in simple elemental and molecular systems subjected static pressures up to >300 GPa, with a focus on the discovery, characterization, synthesis, and recovery of superconductors with very high critical temperatures formed from hydrogen-rich materials. A full range of state-of-the-art experimental in situ high pressure-temperature techniques together with variable magnetic fields are used in the laboratory at UIC and at national user facilities, guided in part by advanced computational methods. The project investigates prototype high Tc hydrides, including lanthanum-based superhydrides, that have been shown exhibit very high-Tc superconductivity in the vicinity of room temperature and 200 GPa; newly predicted more chemically complex superconductors at these pressures; potential light-element high-Tc superconductors stable at lower pressures approaching ambient; and anomalous rare-earth hydrides that exhibit intriguing electronic and possibly superconducting transitions at and near ambient pressures. The research is advancing understanding of the nature and mechanism of the very high-Tc superconductivity in these systems, ultimately leading to potential practical future applications. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2525652 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Russell Hemley | Institution: University of Illinois at Chicago, CHICAGO, IL | Award Amount: $652,461 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2525652 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2525652.html