Sub-terahertz amplification in a semiconductor superlattice with moving charge domains

Sub-terahertz amplification in a semiconductor superlattice with moving charge domains

Spontaneous DC Current Generation in a Resistively Shunted Semiconductor Superlattice Driven by a TeraHertz Field

We study a resistively shunted semiconductor superlattice subject to a highfrequency electric field. Using a balance equation approach that incorporates the influence of the electric circuit, we determine numerically a range of amplitude and frequency of the ac field for which a dc bias and current are generated spontaneously and show that this region is likely accessible to current experiments...

Coherent terahertz sound amplification and spectral line narrowing in a stark ladder superlattice.

The bias voltage applied to a weakly coupled n-doped GaAs/AlAs superlattice increases the amplitude of the coherent hypersound oscillations generated by a femtosecond optical pulse. This bias-induced amplitude increase and experimentally observed spectral narrowing of the superlattice phonon mode with a frequency 441 GHz provides the evidence for hypersound amplification by stimulated emission ...

Coherent Hall effect in a semiconductor superlattice.

The coherent Hall effect denotes the transient Hall response of impulsively excited coherent charge-carrier wave packets in a solid. We report the first experimental study of this phenomenon (i) using a semiconductor superlattice in crossed electric and magnetic fields as a model for three-dimensional materials and (ii) employing a contactless optoelectronic technique to probe the transient cur...

Wave packets in a semiconductor superlattice

A theoretical study of hole wave packets in a GaAs, Als,,Ga,,,As superlattice is presented. Formation of the wave packet by short laser pulse excitation and the time-dependent nature of the wave packet are discussed, with particular attention given to the quasi-periodic nature of the time dependence. Phenomena analogous to those displayed in atomic and molecular wave packet systems are predicte...