Full multiband simulation of quantum electron transport in resonant tunneling devices

• Published in: Solid-state electronics Vol. 44; no. 11; pp. 1939 - 1947
• Main Authors: Ogawa, M., Sugano, T., Miyoshi, T.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2000
• Subjects: Complex band structure; Dyson's equation; Evanescent modes; Mode matching; Non-equilibrium Green's functions; Poisson's equation; Quantum transport; Resonant tunneling diode; Tight-binding approximation; Poisson's equation; Evanescent modes; Tight-binding approximation; Mode matching; Dyson's equation; Resonant tunneling diode; Non-equilibrium Green's functions; Complex band structure; Quantum transport
• ISSN: 0038-1101; 1879-2405
• DOI: 10.1016/S0038-1101(00)00174-X

We present a formulation and calculations of multiband quantum transport of electrons in resonant tunneling diodes (RTDs) based on a non-equilibrium Green function theory. In the formulation we have used an empirical tight-binding method to include a realistic band structure, where evanescent-wave matching at heterointerfaces, Γ– X valley-mixing effects, and space charge effect are duly taken into account. Our results show that the current–voltage characteristics of a GaAs/AlAs double-barrier RTD has a larger current density than the conventional single band (SB) model since the latter is found to overestimate the decay constant in the barriers. Note that matching of evanescent electron modes essentially requires the inclusion of valley-mixing effects for GaAs/AlAs heterostructures owing to breaking of lattice-translational symmetry occurring at interfaces.