Point-contact spectroscopy of the high-temperature superconductor BiSrCaCuO

Abstract

The maximum value of the energy gap $\Delta \simeq 8meV$ and the ratio $2\delta /k{T}_c\simeq 2.5$ are determined for a high-temperature superconductor $\mathrm{B}{\mathrm{i}}_2\mathrm{S}{\mathrm{r}}_2\mathrm{CaC}{\mathrm{u}}_2{\mathrm{O}}_{8+\mathrm{y}}$ 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.

4 pages, 3 figures