Recent Studies in Superconductivity at Extreme Pressures

TL;DR

This paper reviews the progress in high-pressure superconductivity research over 82 years, highlighting how extreme pressures induce significant changes in material properties and superconducting transition temperatures.

Contribution

It provides a comprehensive overview of recent experimental findings in superconductivity at multi-megabar pressures, emphasizing advancements and new phenomena observed.

Findings

Superconducting Tc in metals has reached up to 25 K at high pressures.

High pressures can turn insulators into metals and magnetic materials into superconductors.

Recent experiments have explored superconductivity at pressures exceeding 1 Mbar.

Abstract

Studies of the effect of high pressure on superconductivity began in 1925 with the seminal work of Sizoo and Onnes on Sn to 0.03 GPa and have continued up to the present day to pressures in the 200 - 300 GPa range. Such enormous pressures cause profound changes in all condensed matter properties, including superconductivity. In high pressure experiments metallic elements, Tc values have been elevated to temperatures as high as 20 K for Y at 115 GPa and 25 K for Ca at 160 GPa. These pressures are sufficient to turn many insulators into metals and magnetics into superconductors. The changes will be particularly dramatic when the pressure is sufficient to break up one or more atomic shells. Recent results in superconductivity to Mbar pressures wll be discussed which exemplify the progress made in this field over the past 82 years.