Epitaxially Stabilized EuMoO3: A New Itinerant Ferromagnet

TL;DR

This study demonstrates the successful synthesis of a metastable EuMoO3 thin film via epitaxial stabilization, revealing a new compound with high conductivity and magnetic properties, expanding the possibilities of metastable phase materials.

Contribution

It introduces a novel epitaxial stabilization method to synthesize a new EuMoO3 phase with unique electronic and magnetic properties not achievable in bulk form.

Findings

EuMoO3 exhibits high electrical conductivity.

EuMoO3 shows a large magnetic moment.

Epitaxial stabilization enables formation of metastable phases.

Abstract

Synthesizing metastable phase often opens new functions in materials but is a challenging topic. Thin film techniques have advantages to form materials which do not exist in nature since nonequilibrium processes are frequently utilized. In this study, we successfully synthesize epitaxially stabilized new compound of perovskite Eu2+Mo4+O3 as a thin film form by a pulsed laser deposition. Analogous perovskite SrMoO3 is a highly conducting paramagnetic material, but Eu2+ and Mo4+ are not compatible in equilibrium and previous study found more stable pyrochlore Eu23+Mo24+O7 prefers to form. By using isostructural perovskite substrates, the gain of the interface energy between the film and the substrate stabilizes the matastable EuMoO3 phase. This compound exhibits high conductivity and large magnetic moment, originating from Mo 4d2 electrons and Eu 4f7 electrons, respectively. Our result indi-cates the epitaxial stabilization is effective not only to stabilize crystallographic structures but also to from a new compound which contains unstable combinations of ionic valences in bulk form.