Design of structured La$_{2-x}$Sr$_{x}$CuO$_{4}$ films as superconducting transition-edge sensors at 4.2K

TL;DR

This paper explores structuring La$_{2-x}$Sr$_{x}$CuO$_{4}$ films to enhance their performance as superconducting transition-edge sensors at 4.2K, using computational design to optimize bolometric characteristics.

Contribution

It introduces a computational approach to design structured cuprate films, improving bolometric performance by optimizing carrier density patterns.

Findings

Structuration improves saturation power and dynamic range.

Designs enable bolometric operation in constant current mode.

Finite-element simulations guide optimal structuration patterns.

Abstract

We calculate the effects of carrier-density structuration and patterning on thin films of the cuprate superconductor La$_{2-x}$Sr$_{x}$CuO$_{4}$, in order to optimize its functional characteristics as sensing material for resistive transition-edge bolometers at liquid-He temperature. We perform finite-element computations considering two major contributions to structuration: The intrinsic random nanoscale disorder associated to carrier density nonstoichiometry, plus the imposition of regular arrangements of zones with different nominal carrier densities. Using ad-hoc seek algorithms, we obtain various structuration designs that markedly improve the bolometric performance, mainly the saturation power and dynamic range. Bolometric operation becomes favorable even in the easier-to-implement constant current mode of measurement.