A MICROSCOPIC CALCULATION FOR HOLE TUNNELING IN TYPE-II INAS GASB STRUCTURES

We present a microscopic empirical pseudopotentiai calculation, includ ing the spin-orbit interaction, for hole states in type-II InAs/GaSb s tructures. We consider hole scattering at the single InAs-GaSb interfa ce where the type-II band alignment is such that the conduction band a nd valence band overlap at zero bias. The microscopic results for the amplitude and energy dependence of the scattered currents, carried by the various real bulk bands in the materials of the interface, can be understood by applying time reversal symmetry arguments and by conside ration of the microscopic spatial symmetry of the bulk states that mus t be matched at the interface. We present results for hole tunnelling in the InAs-GaSb-InAs structures, to elucidate the physics of resonant interband tunnelling. The transmission results show the presence of b road resonances due to quasi confined states. We also observe narrow F ano-like resonance features in the hole transmission which are a conse quence of a complicated microscopic quantum interference process.