phonon

https://doi.org/10.1351/goldbook.P04547
Elementary excitation in the quantum mechanical treatment of vibrations in a crystal lattice. An energy bundle that behaves as a particle of energy \(h\ \nu \), with \(\nu \) the vibration frequency and \(h\) the @P04685@.
Notes:
  1. A phonon can be considered as an acoustic @M03958@ of thermal vibration of a crystal lattice (or liquid helium II).
  2. Every harmonic vibration can be decomposed in phonons, which are the elementary vibrations. The total number of phonons in a system that has internal vibrations (e.g., a crystal) is related to the temperature of the system.
  3. The concept of phonons provides a simplification in the theories of thermal and electrical conduction in solids.
  4. For example, interactions between phonons and electrons are thought to be responsible for such phenomena as 'superconductivity'.
Source:
PAC, 2007, 79, 293. (Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)) on page 382 [Terms] [Paper]