Wave packet

"Wave train" redirects here. For the mathematics concept, see Periodic travelling wave.
A looped animation of a wave packet propagating without dispersion: the envelope is maintained even as the phase changes

In physics, a wave packet (also known as a wave train or wave group) is a short burst of localized wave action that travels as a unit, outlined by an envelope. A wave packet can be analyzed into, or can be synthesized from, a potentially-infinite set of component sinusoidal waves of different wavenumbers, with phases and amplitudes such that they interfere constructively only over a small region of space, and destructively elsewhere.[1] Any signal of a limited width in time or space requires many frequency components around a center frequency within a bandwidth inversely proportional to that width; even a gaussian function is considered a wave packet because its Fourier transform is a "packet" of waves of frequencies clustered around a central frequency.[2] Each component wave function, and hence the wave packet, are solutions of a wave equation. Depending on the wave equation, the wave packet's profile may remain constant (no dispersion) or it may change (dispersion) while propagating.

  1. ^ Joy Manners (2000), Quantum Physics: An Introduction, CRC Press, pp. 53–56, ISBN 978-0-7503-0720-8
  2. ^ Schwartz, Matthew. "Lecture 11: Wavepackets and dispersion" (PDF). scholar.harvard.edu. Archived (PDF) from the original on 2023-03-18. Retrieved 2023-06-22.