Non-equilibrium Green function theory is formulated to meet the three main challenges of high bias quantum device modeling: self-consistent charging, incoherent and inelastic scattering, and band structure. The theory is written in a general localized orbital basis using the example of the zinc blende lattice. A Dyson equation treatment of the open system boundaries results in a tunneling formula with a generalized Fisher-Lee form for the transmission coefficient that treats injection from emitter continuum states and emitter quasi-bound states on an equal footing. Scattering is then included. Self-energies which include the effects of polar optical phonons, acoustic phonons, alloy fluctuations, interface roughness, and ionized dopants are derived. Interface roughness is modeled as a layer of alloy in which the cations of a given type cluster into islands. Two different treatments of scattering; self-consistent Born and multiple sequential scattering are formulated, described, and analyzed for numerical tractability. The relationship between the self-consistent Born and multiple sequential scattering algorithms is described, and the convergence properties of the multiple sequential scattering algorithm are numerically demonstrated by comparing with self-consistent Born calculations.

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Influence of doping on the electronic transport in GaSb/InAs(Sb) nanowire tunnel devices Appl. Phys. Lett. 101, 043508 (2012) Simulation of trap-assisted tunneling effect on characteristics of gallium nitride diodes J. Appl. Phys. 111, 123115 (2012) Tuning of terahertz intrinsic oscillations in asymmetric triple-barrier resonant tunneling diodes J. Appl. Phys. 111, 124310 (2012) Repeatable low-temperature negative-differential resistance from Al0.18Ga0.82N/GaN resonant tunneling diodes grown by molecular-beam epitaxy on free-standing GaN substrates Quantitative simulation of an InGaAs/InAlAs resonant tunneling diode is obtained by relaxing three of the most widely employed assumptions in the simulation of quantum devices. These are the single band effective mass model ͑parabolic bands͒, Thomas-Fermi charge screening, and the Esaki-Tsu 1D integral approximation for current density. The breakdown of each of these assumptions is examined by comparing to the full quantum mechanical calculations of self-consistent quantum charge in a multiband basis explicitly including the transverse momentum.

We examine the requirements placed upon the Hamiltonian under the demand of gauge invariance. From these requirements we derive the gauge-invariant form of the tight-binding Hamiltonian with electromagnetic coupling. In our derivation we do not make recourse to a Peierls substitution and hence avoid introducing any ambiguities of path. Our expression transparently reduces to the familiar expression in a complete basis. We apply this Hamiltonian to study resonant magnetotunneling spectroscopy using a simple tight-binding model.

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