Wave Packet Dynamics in a Biased Finite-Length Superlattice

Herbert Kroemer

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arXiv · cond-mat/0310019

Wave Packet Dynamics in a Biased Finite-Length Superlattice

Herbert Kroemer

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Abstract

In a superlattice containing a finite number of periods, the allowed values of the Bloch wave number form a discrete set, and the dynamics of an electron through k-space under the influence of an external force is necessarily that of a superposition wave packet composed of multiple Bloch waves. The present paper investigates this dynamics for a particularly simple class of "k-compact" wave packets, in which the spread over different k-values is minimized, and which propagate with an essentially rigid shape through k-space.

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Herbert Kroemer. 2003-10-01. Wave Packet Dynamics in a Biased Finite-Length Superlattice. https://arxiv.org/abs/cond-mat/0310019

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