EAGER:SUPER: Optically-enhanced superconductivity in hydrogen-based materials

Harvard University, Cambridge MA

Investigators

Abstract

Non-Technical Description Superconductivity – a state of matter in which electrons flow without resistance – is a key ingredient for the development of lossless electrical power transmission, controlled nuclear fusion, and quantum computing. Normally found only at cryogenic temperatures, its stabilization at fully ambient temperatures and pressures represents a major challenge. Recent experiments on hydrogen-rich materials demonstrated room-temperature superconductivity under extreme pressures, thus inching closer to this goal. This project aims to gradually lower the pressure requirements in these materials by modifying their microscopic properties with ultrafast laser pulses. This research may be conducive to the realization of superconductivity at fully ambient conditions and, more broadly, to novel ways to control quantum materials. This tightly integrated experimental and theoretical project involves undergraduate students, graduate students, and postdoctoral researchers, thus contributing to training the next generation of experts in quantum information, photonics, and physical sciences in general. Technical Description Achieving and stabilizing superconductivity at ambient pressure and temperature is a major research focus of modern condensed matter physics and a fundamental step towards its technological applications. Over the last century, efforts to optimize transition temperatures above a few Kelvin were mainly driven by material discovery, either programmatic or serendipitous. More recently, the use of high pressures, heterostructuring, and ultrafast optical fields enabled the observation of superconducting states at ever increasing transition temperatures. However, the goal of reaching stable superconductivity at ambient temperature and pressure is still elusive and requires either completely new experimental approaches or the simultaneous application of multiple tuning knobs. This collaborative experiment-theory project aims to leverage advanced ultrafast optical techniques to dynamically stabilize high-temperature superconductivity at low, or even ambient, pressures in superhydride materials. Following optical excitation, the transient electronic dynamics are monitored through time-resolved reflectivity measurements and mapped as a function of temperature and pressure. This research may potentially be transformative towards the realization of a metastable high-temperature superconductor at ambient pressure and, more broadly, the control of emergent electronic phases in compressed quantum materials. The interdisciplinary nature of the proposed research, at the interface between condensed matter physics, materials science, and photonics, and the tight integration of experiment and theory provide a stimulating educational opportunity for undergraduate/graduate students and postdocs who are supported by this grant. 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.