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Wavefronts may move upstream in doped semiconductor superlattices

A. Carpio·L. L. Bonilla·A. Wacker·E. Schoell
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Abstract

In weakly coupled, current biased, doped semiconductor superlattices, domain walls may move upstream against the flow of electrons. For appropriate doping values, a domain wall separating two electric field domains moves downstream below a first critical current, it remains stationary between this value and a second critical current, and it moves upstream above. These conclusions are reached by using a comparison principle to analyze a discrete drift-diffusion model, and validated by numerical simulations. Possible experimental realizations are suggested.

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A. Carpio, L. L. Bonilla, A. Wacker, E. Schoell. 2000-03-15. Wavefronts may move upstream in doped semiconductor superlattices. https://doi.org/10.1103/physreve.61.4866

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