Time-dependent modeling of resonant-tunneling diodes from direct solution of the Schrödinger equation

Abstract

Numerical solution of the time-dependent Schrödinger equation for resonant-tunneling diodes has been impeded by the difficulty in handling open-system boundary conditions. This paper presents a boundary condition method to simulate the interaction with ideal particle reservoirs at the device boundaries. A switching transient is calculated where the device is switched from the peak current state to the valley current state. In addition, this method was used to develop a small-signal analysis of resonant-tunneling diodes. Results for the small-signal equivalent circuit of a particular device versus frequency are presented.

Resonant-tunneling diode stability and its consequences for high-frequency operation

“…It has been shown from theoretically calculated characteristics that for a particular device the negative conductance remains constant up to about 200 GHz but then starts to decrease and in the terahertz range becomes about half of the DC value [5]. This is certainly device dependent and for some devices the roll off will be much faster.…”

“…al. [5] have shown theoretically that the nonlinearity and negative differential resistance of these devices should persist into the THz frequency range. Sollner et.…”

Time-dependent current response of semiconductor multi-barriers

“…Numerical procedures for handling open boundaries in connection with the Schrödinger equation (SE) have been proposed both for steady-state, Ref. [1], and time-dependent situations, Refs [2,3]. Moreover, a closed-box simulation scheme has been proposed [4,5].…”

Electronic Conductivity in Open Cylindrical Two-Barrier Symmetric Resonance Tunnel Structure

“…This equation can be solved within the approximation of small signal [5][6][7][8][9][10], assuming that the amplitude of the electric field ε is small. Thus, its general solution is written as:…”

“…One of the way of improving it, is to use the open RTS, where the life time of electron quasi-stationary states (QSS) is smaller than the duration of dissipative processes in the system. Such open RTS (mainly quasi-two-dimensional) are investigated for more than ten years using different theoretical models [5][6][7][8][9]. However, the consistent theory of their response is still far from the completion.…”