EAGER: SUPER: Alkane-based molecular synthesis and quantum sensing of light & warm superconductors

University Of Washington, Seattle WA

Investigators

Abstract

Non-technical Summary Superconductors have the potential to transform our society’s future transportation and electricity distribution networks based on their unique ability to conduct electricity without loss due to electrical resistance. Magnetically-levitated trains could transport passengers and cargo efficiently without friction. Superconducting power transmission lines could help lower the overall carbon budgets of advanced, industrialized economies. Normally, materials show superconducting behavior only at low temperatures, well below the freezing point of water. One grand challenge in the field of superconductivity is to discover materials that have superconducting properties at room temperature. In the past decade tremendous progress has been made in demonstrating that metallic and non-metallic materials can show superconductivity had high temperatures (~300K) when they are compressed to pressures on the order of 100,000 atmospheres. With this project, supported by Division of Materials Research, Professor Peter Pauzauskie and his research group at the University of Washington will develop new chemical materials synthesis and processing methods to make high-temperature superconductors from non-metallic elements (carbon, hydrogen, sulfur) that could also maintain their superconducting properties at atmospheric pressure. Materials will be synthesized based on the use of molecular alkane precursors exposed to large pressures within a diamond anvil cell. Nitrogen impurities within the diamond anvils will be used to detect the transition to a superconducting state based on optically detected magnetic resonance. The atomic microstructure of the materials recovered from high pressure will be characterized using isotopically sensitive microscopy. Technical Summary In the past 10 years tremendous progress has been made in the discovery of materials at high pressure that exhibit a superconducting phase transition at warm temperatures based on binary metal-hydride and ternary non-metallic hydrogenated materials. If the pressure required to observe superconductivity could be lowered to atmospheric pressure, then these materials would have the potential to revolutionize the nation’s public transportation networks, the nation’s electrical energy distribution grid, and also national synchrotron-based scientific user facilities. Currently there is no fundamental scientific knowledge to realize materials capable of demonstrating superconductivity at both 1) room temperature and 2) atmospheric pressure. Recently room-temperature superconductivity has been reported at high (GPa) pressures for hydrogenated carbon sulfide (HCS) materials, however the atomistic microstructure of these materials remains a mystery. This project, supported by the Division of Materials Research, will test the high-risk, high-reward hypothesis that saturated molecular alkanes (CnX2n+2, X = H, D) can be used to create low-cost HCS room temperature superconductors without the need for molecular hydrogen. The central hypothesis that will be tested experimentally is that molecular materials can serve as a hydrogen source that will enable the formation of hydrogen-carbon-sulfur room temperature superconductors at atmospheric pressure through the atomically precise doping of hydrogen within high-surface-area, carbonaceous starting materials. This hypothesis will be tested with a unique experimental design based on 1) atomically precise, molecular alkane-based delivery of hydrogen, 2) high-pressure, high-temperature materials synthesis, 3) in situ quantum sensing of superconducting phase transitions based on optically detected magnetic resonance, and 4) ex situ atom probe tomography for quantitative microstructural characterization of recovered product materials. 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.