Universal quantum transition from superconducting to insulating states in pressurized Bi2Sr2CaCu2O8+{\delta} superconductors

TL;DR

This study reveals a universal quantum transition from superconducting to insulating-like states under pressure across various Bi-based cuprate superconductors, challenging existing theories of their phase behavior.

Contribution

It demonstrates a universal pressure-induced quantum transition in multiple cuprate superconductors, providing new insights into their phase diagram and underlying physics.

Findings

Universal transition observed in Bi2212, Bi2201, and Bi2223 superconductors.

Transition occurs from superconducting to insulating-like state under pressure.

Results challenge the conventional metallic phase assumption after suppression of superconductivity.

Abstract

Copper oxide superconductors have continually fascinated the communities of condensed matter physics and material sciences because they host the highest ambient-pressure superconducting transition temperature (Tc) and mysterious physics. Searching for the universal correlation between the superconducting state and its normal state or neighboring ground state is believed to be an effective way for finding clues to elucidate the underlying mechanism of the superconductivity. One of the common pictures for the copper oxide superconductors is that a well-behaved metallic phase will present after the superconductivity is entirely suppressed by chemical doping or application of the magnetic field. Here, we report a different observation of universal quantum transition from superconducting state to insulating-like state under pressure in the under-, optimally- and over-doped Bi2212 superconductors with two CuO2 planes in a unit cell. The same phenomenon has been also found in the Bi2201 superconductor with one CuO2 plane and the Bi2223 superconductor with three CuO2 planes in a unit cell. These results not only provide fresh information but also pose a new challenge for achieving a unified understanding on the underlying physics of the high-Tc superconductivity.