Investigation of the Tunneling Spectra in HgBr2-Intercalated Bi-2212 Single Crystals below and above Tc

TL;DR

This study investigates the tunneling spectra of HgBr2-intercalated Bi-2212 single crystals across a wide temperature range, revealing that the superconducting gap persists as a pseudogap above the critical temperature, T_c.

Contribution

It provides experimental evidence that the superconducting gap evolves into a pseudogap above T_c in HgBr2-intercalated Bi-2212 crystals, expanding understanding of high-temperature superconductivity.

Findings

Superconducting gap features persist above T_c.

Spectral features indicate gap evolution into a pseudogap.

Tunneling conductance measurements support pseudogap presence.

Abstract

Interlayer tunneling spectroscopy measurements were performed on mesa arrays of Bi-2212 single crystals, intercalated with HgBr$_2$. Tunneling conductances were obtained over a wide temperature range to examine the spectral features, especially the behavior of the quasiparticle peaks corresponding to superconducting energy gaps (SGs). Experimental spectra showed that gap-like features are still present even for the temperatures far above the transition temperature, T$_c$. This evidence is consistent with the idea that the SG evolves into a pseudogap above T$_c$ for HgBr$_2$-intercalated Bi-2212 single crystals.