Boundaries, transients and multiple barrier devices

Wigner Function Methods in Modeling of Switchingin Resonant Tunneling Devices

“…For very high values of bias the numerical noise in Wigner function was again absent. As reported earlier, this calculation did not show hysteresis in the dc characteristics [2]. In a supplementary calculation with a device length of 100nm, and the same number of spatial and momentum grid points, the reduction in length resulted in an increased range for the momentum wave vector and a corresponding increase in the spatial resolution.…”

“…Given this, what is the best approach to studying transients? The best approach should be ascertained pragmatically; constrained by how much can be done in an acceptable period of time, and the knowledge base. In the past the approach we have taken [1] has included: (i) studies of the quantum hydrodynamic equations, (ii) the density matrix in the coordinate representation, and (iii) the Wigner distribution function [2]. Of the three the weakest is the quantum hydrodynamics derived as quantum corrections [3].…”

A wigner function-based quantum ensemble monte carlo study of a resonant tunneling diode

“…Furthermore, the peak and valley locations are approximately where expected. It is of interest that our simulations do not show any hysteresis [22]. The reason for the NDR is that as the device is biased, the conduction band (CB) in the contacts begins to sweep past the resonant level inside the well.…”

Transient Analysis of Silicon Devices Using the Hydrodynamic Model

“…In recent years increasing attention has been paid to the analysis of the switching behaviour of submicron devices, bringing about the necessity of extending the solution of the Hydrodynamic Model (HD) to the transient case [1,2]. The Hydrodynamic Model in the transient case reads [3]:…”