Incandescence and energy bands

[monstersaurou]

In an incandescent lamp, only the electrons at the top of the band can participate.

Got this from wikipedia but I don't quite understand what it means.

From what I know regarding incandescence, it is basically the vibrational emission spectrum of a solid lattice produced when the lattice is heated up. This spectrum is continuous and contains all wavelengths of light, although they are of different intensities, as described by Planck's law. In all, it is a phenomenon which can be accounted for by considering the interactions that occur at the level of the aggregate lattice structure of the solid, not at the level of individual atoms and molecules.

Wiki mentions 'top of the band' here. Are they referring to valence and conduction bands? Is this related to the fact that in considering incandescence, we've got to consider the solid as an aggregate lattice structure, not individual particles? If so, how can valence and conduction bands be used to further explain incandescence beyond such reasoning as that I've put forth?

 

[ZapperZ]

Thank you for bringing out another example of why one should not use Wikipedia as a valid reference.

Your view is more accurate. This has been discussed before in several threads, the latest of which can be found here:

https://www.physicsforums.com/showthread.php?t=282969

Zz.

 

[Entropia]

I can provide an explanation for the concept of incandescence and its relationship to energy bands. Incandescence is the emission of light from a heated object, such as a solid lattice. The emission spectrum of this light is continuous, meaning it contains all wavelengths of light, and is governed by Planck's law.

The "top of the band" refers to the energy bands of the solid lattice. In a solid, the electrons are arranged in energy bands, with the valence band being the lowest energy level and the conduction band being the highest energy level. When a solid is heated, the electrons in the valence band gain enough energy to jump to the conduction band, leaving behind a "hole" in the valence band. This movement of electrons creates the continuous emission spectrum of incandescence.

However, not all electrons in the valence band can participate in this process. Only the electrons at the top of the band, closest to the conduction band, have enough energy to jump to the conduction band and emit light. This is because the energy levels of the electrons in the valence band are discrete, and only those at the top of the band have enough energy to overcome the band gap and reach the conduction band.

In summary, the concept of energy bands helps explain the phenomenon of incandescence by showing how the movement of electrons within a solid lattice leads to the emission of light. It also explains why only certain electrons at the top of the valence band can participate in this process.