Exploring broken time-reversal symmetry in Cd₃As₂/(Ga,Mn)Sb Dirac semimetal/ferromagnetic semiconductor heterostructures

Cd₃As₂ has attracted attention as a canonical Dirac semimetal. In this study, we aim to break time reversal symmetry (TRS) in Cd₃As₂ by interfacing with a ferromagnetic semiconductor, (Ga,Mn)Sb. We have grown epitaxial Cd₃As₂ /(Ga,Mn)Sb bilayers using molecular beam epitaxy on GaSb (111) buffer layers deposited on GaAs (111)B substrates. High-resolution x-ray diffraction shows good crystalline quality of GaSb and Cd₃As₂ layers with full width half maximum of rocking curves, 0.04° and 0.11°, respectively. Atomic force microscopy shows smooth surfaces of (Ga,Mn)Sb and Cd₃As₂ with root mean square roughness ~ 1.3 nm. SQUID magnetometry reveals that (Ga,Mn)Sb films are ferromagnetic, while low temperature magnetoresistance data show that they are highly resistive for the Mn composition used. We report the temperature dependent magneto-transport properties in these Cd₃As₂ /(Ga,Mn)Sb heterostructures and investigate the magnetic proximity effect by varying the thickness of the Cd₃As₂ layer. We are also exploring interfacing Cd₃As₂ with other ferromagnetic semiconductors in order to find an efficient material for breaking TRS in Cd₃As₂.