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Absorption of light by solids: How is the energy (in electron-volts) carried by light with a wavelength, of say 514 nm, exchanged with the solid? What will be created in the solid by the absorption? What effect would the existence of an energy gap have?

This question is related to an experiment I have to do related to Bandgaps, but I don't seem to know the answer to it?

I know that electrons in the atoms of the solid get excited and thus the energy is transformed into heat, but this doesn't mention any band gaps in the solid.

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In a solid in equilibrium, electrons occupy allowed states in energy-momentum space called energy bands according to the Fermi-Dirac statistics. Light (photon) absorption by an electron occurs, when the electron in an occupied state is moved to a higher unoccupied state, just like in an atom. In such a transition both energy and momentum have to be conserved, which often requires the participation of phonons in such a transition. In a solid with a bandgap, there is a forbidden energy range usually between energy bands almost completely occupied with electrons and energy bands that are almost completely unoccupied. This means that a certain minimum energy has to be provided (by the photon) to enable electrons to jump from the filled lower band to the empty higher band. This causes an "absorption edge" for light when its photon energy surpasses the bandgap energy.

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