Visualizing the phonon wave function

Author Info

Scott C. Johnson, University of California - Davis
Thomas D. Gutierrez, University of California - Davis

Recommended Citation

Postprint version. Published in American Journal of Physics, Volume 70, Issue 3, March 1, 2002, pages 227-237.

NOTE: At the time of publication, the author Thomas Gutierrez was not yet affiliated with Cal Poly.

The definitive version is available at https://doi.org/10.1119/1.1446858.

Abstract

A phonon often is described as ‘‘a quantum of lattice vibration,’’ but this description can be difficult to reconcile with the wave functions explored in a typical undergraduate quantum mechanics class. A phonon wave function is similar to the harmonic oscillator wave functions studied in introductory quantum mechanics, except that it is many-dimensional. We suggest a way to visualize the probability density for this very high-dimensional wave function. The resulting pictures are especially clear and intuitive for a coherent state, which is both a good approximation to a sound wave and a discrete analog to laser light. These pictures can also provide a qualitative introduction to quantum field theory.

Disciplines

Physics

Copyright

2002 American Association of Physics Teachers.

Publisher statement

This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Association of Physics Teachers. The following article appeared in American Journal of Physics.