Molecular beam deposition of a new layered pnictide with distorted Sb square nets

TL;DR

This paper reports the synthesis of a new layered pnictide, EuCdSb₂, using molecular beam deposition, revealing its orthorhombic structure and antiferromagnetic properties, advancing the development of Dirac materials.

Contribution

First successful fabrication of EuCdSb₂ thin films with the largest B-site ionic radius, enabling exploration of novel Dirac materials.

Findings

EuCdSb₂ crystallizes in an orthorhombic Pnma structure

Exhibits antiferromagnetic ordering at 15K

First thin film synthesis of this compound

Abstract

While the family of layered pnictides $ABX_2$ ($A$ : rare or alkaline earth metals, $B$ : transition metals, $X$ : Sb/Bi) can host Dirac dispersions based on Sb/Bi square nets, nearly half of them has not been synthesized yet for possible combinations of the $A$ and $B$ cations. Here we report the fabrication of EuCdSb$_{\mathrm{2}}$ with the largest $B$-site ionic radius, which is stabilized for the first time in thin film form by molecular beam deposition. EuCdSb$_{\mathrm{2}}$ crystallizes in an orthorhombic $Pnma$ structure and exhibits antiferromagnetic ordering of the Eu magnetic moments at $T_\mathrm{N}=15$K. Our successful growth will be an important step for further exploring novel Dirac materials using film techniques.