posted on 2017-08-11, 15:22authored byAnton O. Sel'skii, Alexey A. Koronovskii, Alexander E. Hramov, Olga I. Moskalenko, Kirill Alekseev, Mark GreenawayMark Greenaway, F. Wang, T.M. Fromhold, Aleksei V. Shorokhov, Nikolai N. Khvastunov, Alexander BalanovAlexander Balanov
We show that resonant electron transport in semiconductor superlattices with an applied electric and tilted magnetic field can, surprisingly, become more pronounced as the lattice and conduction electron temperature increases from 4.2 K to room temperature and beyond. It has previously been demonstrated that at certain critical field parameters, the semiclassical trajectories of electrons in the lowest miniband of the superlattice change abruptly from fully localized to completely unbounded. The unbounded electron orbits propagate through intricate web patterns, known as stochastic webs, in phase space, which act as conduction channels for the electrons and produce a series of resonant peaks in the electron drift velocity versus electric-field curves. Here, we show that increasing the lattice temperature strengthens these resonant peaks due to a subtle interplay between the thermal population of the conduction channels and transport along them. This enhances both the electron drift velocity and the influence of the stochastic webs on the current-voltage characteristics, which we calculate by making self-consistent solutions of the coupled electron transport and Poisson equations throughout the superlattice. These solutions reveal that increasing the temperature also transforms the collective electron dynamics by changing both the threshold voltage required for the onset of self-sustained current oscillations, produced by propagating charge domains, and the oscillation frequency.
Funding
The work was supported by the Federal special purpose programme “Scientific and educational personnel of innovation Russia (2009 - 2013)”, the UK Engineering and Physical Sciences Research Council and the “Dynasty” Foundation.
History
School
Science
Department
Physics
Published in
Physical Review B - Condensed Matter and Materials Physics
Volume
84
Issue
23
Citation
SEL'SKII, A.O., 2011. Effect of temperature on resonant electron transport through stochastic conduction channels in superlattices. Physical Review B - Condensed Matter and Materials Physics, 84 (23), 235311.
This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
Publication date
2011
Notes
This paper was accepted for publication in the journal Physical Review B - Condensed Matter and Materials Physics and the definitive published version is available at http://dx.doi.org/10.1103/PhysRevB.84.235311.