Fabrication and physical properties of the zero-gap half-metallic Cr3Si film with a DO3 structure

Abstract

This study demonstrates the synthesis of single-phase Cr3Si thin films featuring a highly ordered DO3 structure via magnetron sputtering. The structural, magnetic, and electrical transport properties of the films were systematically investigated. Experimental results reveal that the Cr3Si film crystallizes with a high degree of atomic order, achieving a saturation magnetization that is very consistent with the theoretical value of 2 μB obtained by first-principles calculations. The Cr3Si film manifests a Curie temperature of 350 K, substantially exceeding ambient conditions, thereby enabling robust room-temperature spintronic functionality. The linear magnetoresistance, crossover of magnetoresistance, and almost temperature-independent carrier concentration are observed and further confirm the zero-gap half-metallic nature of the Cr3Si film. Importantly, the introduction of a Cr buffer layer facilitates the growth of the Cr3Si film in the DO3 structure with higher atomic order and reduces the crystallization temperature. The epitaxial interface of Cr/Cr3Si does not affect the electron spin polarizability of the Cr3Si layer, preserving its zero-gap half-metallic properties. The Cr buffer layer maintains its intrinsic antiferromagnetic ordering, thereby establishing a ferromagnetic/antiferromagnetic heterojunction with the Cr3Si layer.