Robust Manipulation of Magnetic Properties in (Ga,Mn)As

Abstract

As one of the representative materials in the field of semiconductor spintronics, dilute magnetic semiconductor (Ga,Mn)As has been intensively studied for more than two decades. The most prominent label of (Ga,Mn)As might be its carrier-mediated ferromagnetism, while its carrier density is several orders of magnitude lower than that in common metals. Parallel with the efforts of enhancing its Curie temperature to above room temperature, exploration of its rich spin-related concepts and physics has also generated many new discoveries, among which controlling its magnetic properties with diverse methods has been one of the most intriguing topics. In this chapter, we attempt to comprehensively assess the progress achieved in manipulating the magnetic properties of (Ga,Mn)As. At first, a brief introduction of the research background, especially the motivation for pursuing robust manipulation of magnetism, will be presented. We will then review the splendid electric field effects on the magnetic properties of (Ga,Mn)As in the second section, in which the endeavor of breaking the ceiling of gating technique determined by the breakdown strength and electric permittivity of dielectrics are discussed. In the third section, we describe methods that utilize light and mechanical strain to alter magnetism, taking advantage of the specific band structure of (Ga,Mn)As (i.e., the existence of a band gap and the strain-mediated band structures). And a new pathway of utilizing self-assembled organic molecules to tune the magnetism in (Ga,Mn)As will be illustrated in the fourth section, which seems to have the possibility of further extending the boundary of previous techniques. This review will end with a summary of challenges and a discussion of future opportunities.