Greenaway_Acoustic waves_PRB10.pdf (740.37 kB)
Download fileUsing acoustic waves to induce high-frequency current oscillations in superlattices
journal contribution
posted on 2013-08-19, 12:23 authored by Mark GreenawayMark Greenaway, Alexander BalanovAlexander Balanov, D.R. Fowler, A.J. Kent, T.M. FromholdWe show that gigahertz acoustic waves in semiconductor superlattices can induce terahertz (THz) electron dynamics that depend critically on the wave amplitude. Below the threshold amplitude, the acoustic wave drags electrons through the superlattice with a peak drift velocity overshooting that produced by a static electric field. In this regime, single electrons perform drifting orbits with THz frequency components. When the wave amplitude exceeds the critical threshold, an abrupt onset of Bloch-type oscillations causes negative differential velocity. The acoustic wave also affects the collective behavior of the electrons by causing the formation of localized electron accumulation and depletion regions, which propagate through the superlattice, thereby producing self-sustained current oscillations even for very small wave amplitudes. We show that the underlying single-electron dynamics, in particular, the transition between the acoustic wave dragging and Bloch oscillation regimes, strongly influence the spatial distribution of the electrons and the form of the current oscillations. In particular, the amplitude of the current oscillations depends nonmonotonically on the strength of the acoustic wave, reflecting the variation in the single-electron drift velocity.
History
School
- Science
Department
- Physics
Citation
GREENAWAY, M.T. ... et al, 2010. Using acoustic waves to induce high-frequency current oscillations in superlattices. Physical Review B, 81 (23), 235313.Publisher
© The American Physical SocietyVersion
- VoR (Version of Record)
Publication date
2010Notes
This article was published in the journal Physical Review B [© The American Physical Society]. It is also available at: http://dx.doi.org/10.1103/PhysRevB.81.235313ISSN
1098-0121Publisher version
Language
- en