Bloch gain in dc-ac-driven semiconductor superlattices in the absence of electric domains

Details Bloch gain in dc-ac-driven semiconductor superlattices in the absence of electric domains Bloch gain in dc-ac-driven semiconductor superlattices in the absence of electric domains

2007-12-19

arxiv.org/abs/0712.3211v1

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

13 pages, 12 figures

Scientific paper

10.1103/PhysRevB.77.165330

We study theoretically the feasibility of amplification and generation of terahertz radiation in dc-ac-driven semiconductor superlattices in the absence of electric domains. We find that if in addition to dc bias a strong THz pump field is applied, Bloch gain profile for a small THz signal can be achieved under conditions of positive static differential conductivity. Here the positive differential conductivity arises, similarly to the case of large-signal amplification scheme [H. Kroemer, cond-mat/0009311)], due to modifications of dc current density caused by the application of high-frequency ac field [K. Unterrainer \textit{et al.}, Phys. Rev. Lett. \textbf{76}, 2973 (1996)]. Whereas the sign of absorption at low and zero frequencies is sensitive to the ac fields, the gain profile in the vicinity of gain maximum is robust. We suggest to use this ac-induced effect in a starter for THz Bloch oscillator. Our analysis demonstrates that the application of a short THz pulse to a superlattice allows to suppress the undesirable formation of electric domains and reach a sustained large-amplitude operation of the dc-biased Bloch scillator.

Affiliated with

Also associated with

No associations

Rating

Bloch gain in dc-ac-driven semiconductor superlattices in the absence of electric domains does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Bloch gain in dc-ac-driven semiconductor superlattices in the absence of electric domains, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bloch gain in dc-ac-driven semiconductor superlattices in the absence of electric domains will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-147091