arXiv:0906.3938 · Progress of Theoretical Physics

On Coherence Lengths of Wave Packets

K. Ishikawa, Y. Tobita

Published Nov 1, 2009• 6 citations

Abstract

The coherence lengths of one-particle states described using quantum wave functions are studied. We show that one particle states in various situations are not described using simple plane waves but using wave packets that are superpositions of plane waves. A wave packet is an approximate eigenstate of the free Hamiltonian and has a finite spatial size that we call the coherence length. The coherence lengths in the coordinate space and momentum space are studied in this paper. We investigate several mechanisms of forming wave packets, stabilities of wave packets, and transformations of wave packets.

DOI: 10.1143/ptp.122.1111

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