Pulsed Laser Deposition of High-Quality Thin Films of the Insulating Ferromagnet EuS

TL;DR

This paper reports the successful fabrication of high-quality EuS thin films with ferromagnetic and insulating properties using pulsed laser deposition, enabling potential new device applications.

Contribution

First demonstration of high-quality EuS thin films with combined ferromagnetic and insulating properties via pulsed laser deposition.

Findings

Films exhibit ferromagnetism below 15.9 K

Films are truly insulating with extremely high resistance

Achieved atomic-scale smoothness and single orientation

Abstract

High-quality thin films of the ferromagnetic-insulator europium(II) sulfide (EuS) were fabricated by pulsed laser deposition on Al2O3 (0001) and Si (100) substrates. A single orientation was obtained with the [100] planes parallel to the substrates, with atomic-scale smoothness indicates a near-ideal surface topography. The films exhibit uniform ferromagnetism below 15.9 K, with a substantial component of the magnetization perpendicular to the plane of the films. Optimization of the growth condition also yielded truly insulating films with immeasurably large resistance. This combination of magnetic and electric properties open the gate for novel devices that require a true ferromagnetic insulator.