Fabrication of FeSe1-x superconducting films with bulk properties

TL;DR

This study reports the successful fabrication of high-quality FeSe1-x superconducting films with bulk-like properties and critical temperatures around 11-12 K using pulsed laser deposition on various substrates, highlighting the importance of growth orientation.

Contribution

The paper demonstrates a method to produce FeSe1-x films with high Tc and preferred (101) orientation, achieving bulk-like superconducting properties on multiple substrates.

Findings

FeSe1-x films with Tc of 11-12 K were fabricated.

Films grown on SrTiO3 exhibited the highest upper critical field of 56 T.

High substrate temperature and (101) orientation are key to high Tc.

Abstract

We have fabricated high-quality FeSe1-x superconducting films with a bulk Tc of 11-12 K on different substrates, Al2O3(0001), SrTiO3(100), MgO(100), and LaAlO3(100), by using a pulsed laser deposition technique. All the films were grown at a high substrate temperature of 610 oC, and were preferentially oriented along the (101) direction, the latter being to be a key to fabricating of FeSe1-x superconducting thin films with high Tc. According to the energy dispersive spectroscopy data, the Fe:Se composition ratio was 1:0.90+-0.02. The FeSe1-x film grown on a SrTiO3 substrate showed the best quality with a high upper critical magnetic field [Hc2(0)] of 56 T.