Molecular beam epitaxy growth of the highly conductive oxide SrMoO$_3$

TL;DR

This paper reports the successful growth of high-quality, highly conductive SrMoO$_3$ thin films using molecular beam epitaxy, with improved electrical properties verified by ARPES, facilitated by buffer layers to enhance film quality.

Contribution

It introduces a novel MBE growth process for SrMoO$_3$ with buffer layers, achieving superior film quality and conductivity compared to previous methods.

Findings

Enhanced electrical conductivity of SrMoO$_3$ films.

Buffer layers improve film surface quality.

Clear Fermi surfaces observed in ARPES measurements.

Abstract

SrMoO$_3$ is a promising material for its excellent electrical conductivity, but growing high-quality thin films remains a challenge. Here we synthesized epitaxial films of SrMoO$_3$ using the molecular beam epitaxy (MBE) technique under a low oxygen-flow rate. Introduction of SrTiO$_3$ buffer layers of 4--8 unit cells between the film and the (001)-oriented SrTiO$_3$ or KTaO$_3$ substrate was crucial to remove impurities and/or roughness of the film surface. The obtained film shows improved electrical conductivities as compared with films obtained by other techniques. The high quality of the SrMoO$_3$ film is also verified by angle-resolved photoemission spectroscopy (ARPES) measurements showing clear Fermi surfaces.