Point-contact spectroscopy of the high-temperature superconductor BiSrCaCuO

TL;DR

This study uses point-contact spectroscopy to measure the energy gap of the high-temperature superconductor Bi2Sr2CaCu2O8+y, revealing a stable modified state with a reduced gap under quasiparticle injection.

Contribution

First to determine the energy gap and its ratio in Bi2Sr2CaCu2O8+y using point-contact spectroscopy and observe a stable modified state induced by quasiparticle injection.

Findings

Energy gap Δ ≈ 8 meV identified

Ratio 2Δ/kT_c ≈ 2.5 measured

Superconductor transitions to a stable modified state under current injection

Abstract

The maximum value of the energy gap $\Delta\simeq 8\ meV$ and the ratio $2\delta/kT_c\simeq~2.5$ are determined for a high-temperature superconductor $\rm Bi_2Sr_2CaCu_2O_{8+y}$ by using point contacts. It was found that the high-temperature superconductor is transformed under the effect of current injection of quasiparticles to a new modified state with a reduced gap, which is stable in a wide range of injection intensity.