Epitaxial growth and transport properties of Sr$_2$CrWO$_6$ thin films

TL;DR

This paper reports on the successful epitaxial growth of high-quality Sr$_2$CrWO$_6$ thin films using Pulsed Laser Deposition, and investigates their structural and transport properties, including magnetic transition temperature.

Contribution

It demonstrates the growth of epitaxial Sr$_2$CrWO$_6$ films with high crystalline quality and explores their magnetic and electrical behavior, despite the lack of sublattice order.

Findings

Curie temperature exceeds 400 K

High crystalline quality achieved on SrTiO$_3$ substrates

Substrate surface undergoes insulator-metal transition during growth

Abstract

We report on the preparation and characterization of epitaxial thin films of the double-perovskite Sr$_2$CrWO$_6$ by Pulsed Laser Deposition (PLD). On substrates with low lattice mismatch like SrTiO$_3$, epitaxial Sr$_2$CrWO$_6$ films with high crystalline quality can be grown in a molecular layer-by-layer growth mode. Due to the similar ionic radii of Cr and W, these elements show no sublattice order. Nevertheless, the measured Curie temperature is well above 400 K. Due to the reducing growth atmosphere required for double perovskites, the SrTiO$_3$ substrate surface undergoes an insulator-metal transition impeding the separation of thin film and substrate electric transport properties.