Talk:Phonon

single phonon detection

A recent edit indicates that single phonons are not detectable, but a web search finds many papers on them. It is convenient that many photons have energies that we can detect, especially in the visible optical range. Partly that is because a single molecule in our eye needs to detect one. But low energy photons are not individually detectable, such as those at radio frequencies. And for phonons, higher frequencies are individually detectable, and low frequency ones not detectable. Gah4 (talk) 05:36, 10 June 2023 (UTC)

Origin of the name

The introduction tells us, without citation, that the concept of phonons was introduced in 1932 by Soviet physicist Igor Tamm. Does anyone know which publication this refers to?

On the other hand, the book Twentieth century physics, Vol. I (p.1302) tells us that the name phonon was introduced by Frenkel in his 1932 book Wave mechanics: Elementary theory to ridicule the notion of a photon. If someone has access to that book, it would be interesting to know exactly what Frenkel writes on the subject. Jähmefyysikko (talk) 06:14, 10 June 2023 (UTC)

superconductivity

This article says

Phonons have also been predicted to play a key role in superconductivity in materials and the prediction of superconductive compounds

whereas Britannica says

phonons are essential in the phenomenon of superconductivity... In superconducting metals at sufficiently low temperatures, however, electrons—which ordinarily repel each other—slightly attract each other through the intermediate effect of phonons. The result is that the electrons move through the material as a coherent group and no longer lose energy through individual collisions. Once this superconducting state has been achieved, any initial flow of electrical current will persist indefinitely. Espoo (talk) 06:09, 19 August 2023 (UTC)

BCS theory uses phonons in its explanation. Among others, the transition temperature, Tc, is dependent on the isotope mass, which couples to phonons. Gah4 (talk) 09:18, 28 February 2024 (UTC)

Individual detection

I removed: However, photons are fundamental particles that can be individually detected, whereas phonons, being quasiparticles, are an emergent phenomenon. For those interested, the removed reference is here. Gah4 (talk) 09:05, 28 February 2024 (UTC)

References