In-situ measurement of self-heating in intrinsic tunnelling spectroscopy

TL;DR

This study combines simultaneous tunnelling and temperature measurements in Bi-2212 structures to distinguish genuine electronic gaps from self-heating artifacts, enhancing the reliability of intrinsic tunnelling spectroscopy.

Contribution

It introduces a method for in-situ temperature monitoring during tunnelling measurements, enabling clearer differentiation between true spectral features and heating effects.

Findings

Self-heating artifacts can mimic electronic gaps.

Size dependence affects tunnelling measurements.

Improved techniques can enhance spectral accuracy.

Abstract

Using advanced sample engineering we performed simultaneous measurement of intrinsic (interlayer) tunnelling characteristics and in-situ monitoring of temperature in small Bi-2212 mesa structures. Together with a systematic study of size-dependence of intrinsic tunnelling, this allowed an unambiguous discrimination between artifacts of self-heating and gaps in electronic spectrum of Bi-2212 High-$T_c$ superconductor. Finally, we analyze the reliability of intrinsic tunnelling spectroscopy and discuss how it can be improved.