Feasibility of a semiconductor superlattice oscillator based on quenched domains for the generation of submillimeter waves

Abstract

We discuss the feasibility of a semiconductor superlattice oscillator which exploits the quenching of propagating dipole domains for the generation of submillimeter waves. We studied the dynamics of electrons in a semiconductor superlattice by performing a simulation based on a drift-diffusion model, taking into account feedback from a resonant circuit. The simulation delivers propagating dipole domains which are quenched before they reach the anode. The periodic formation and quenching of domains creates a self-sustained oscillation of the current through the superlattice. The frequency of the oscillation can be more than three times higher than without feedback. We suggest that with already existing superlattices an oscillator working in the quenched domain mode can be realized up to almost 500 GHz.

Исследование Влияния Случайных Флуктуаций Концентрации Легирующей Примеси На Ток В Полупроводниковых Сверхрешетках

“…Сверхрешетки слу-жат удобной моделью для изучения различных квантово-механических эффектов [3,4]. Не меньший интерес вызывает коллективная динамика электронов при приложении к сверхрешетке постоянного напряже-ния, поскольку в этом случае в структуре могут образовываться пространственно-временные электронные структуры, называемые до-менами (по аналогии с доменами в диоде Ганна [5,6]). Прохож-дение доменов через полупроводниковую сверхрешетку приводит к возникновению колебаний тока, протекающего через структуру, частота которых составляет, как правило, несколько десятков гигагерц [7,8].…”

Miniband transport and oscillations in semiconductor superlattices

“…The electron density obeys a reduced evolution equation (8) in which the functionals N (m) (n) are chosen so that the f (m) (k; n) are bounded and 2π/l-periodic in k. An explicit expression can be easily obtained. We integrate equation (1) with respect to k, thereby getting the charge continuity equation…”

“…Models based on drift-diffusion equations (DDEs) typically use a drift velocity obtained from a simplified kinetic equation and a diffusion coefficient that obeys the Einstein relation [8]. The resulting model is a variant of the well-known Kroemer DDE for the Gunn effect in bulk n-GaAs [9].…”

Negative differential resistance devices for generation of terahertz radiation

“…SLEDs utilize this effect to produce the NDR at the frequency of interest. SLEDs have received much attention since the 1990s [14] because the underlying Bloch effect is associated with much shorter time constants than those of the transferred-electron effect, for example, in GaAs Gunn devices [15].…”