Ferromagnetic Order in Semiconducting Cr‐Doped α‐MnTe Nanosheets Grown by Chemical Vapor Deposition

Abstract

AbstractFerromagnetic semiconductors (FMSs) have been extensively investigated to fulfill the prospect of simultaneous control spin and charge of electron over the past decades. However, it is still highly desirable to identify new ferromagnetic semiconductors with robust and reliable sign of coexistence of semi‐conductivity and ferromagnetism, especially for those ultrathin film systems with great potential for electrical gating. Here, ultrathin Cr‐doped α‐MnTe nanosheets can be readily prepared via a facile chemical vapor deposition (CVD) method, which sustain the crystal structure of parent α‐MnTe but exhibit utterly changed electrical and magnetic properties. Derived from anomalous Hall measurements, the CVD‐grown sample presented a robust out‐of‐plane ferromagnetic order with Curie temperature of ≈210 K and a large coercivity >3.5 T at 2 K. Additionally, Cr‐doped α‐MnTe nanosheets show tunable ferromagnetism and different gating effects with varied thicknesses. The theoretical calculation is performed to explain the origin of its ferromagnetism and semi‐conductivity, probably attributed to the specific antiferromagnetic arrangement of each Mn/Cr plane and non‐zero net magnetic moment with Cr introducing. The work sheds new light on the development of dilute ferromagnetic semiconductors and spintronics.