Manipulating composition gradient in cuprate superconducting thin films

TL;DR

This study demonstrates a precise method for creating compositional gradients in cuprate superconducting films, enabling detailed exploration of doping effects on superconductivity within a single sample.

Contribution

It introduces a controlled moving mask technique to synthesize combinatorial superconducting films with a linear doping gradient on a single substrate.

Findings

Doping levels vary monotonically along the film.

Micro-region x-ray diffraction confirms doping gradient accuracy.

Numerical simulation matches the linear doping variation.

Abstract

The techniques of growing films with different parameters in single process make it possible to build up a sample library promptly. In this work, with a precisely controlled moving mask, we synthetized superconducting La2-xCexCuO4+/-{\delta} combinatorial films on one SrTiO3 substrate with the doping levels from x = 0.1 to 0.19. The monotonicity in doping along the designed direction is verified by micro-region x-ray diffraction and electric transport measurements. More importantly, by means of numerical simulation, the real change of doping levels is in accordance with a linear gradient variation of doping levels in the La2-xCexCuO4+/-{\delta} combinatorial films. Our results indicate that it is promising to accurately investigate materials with critical composition by combinatorial film technique.