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Is there an intuitive explanation of how the crystal momentum can change to excite an electron from the valence band to the conduction band?

How does a photon change the crystal momentum of an electron to push it up to the conduction band? How does it work on the quantum scale of things?

From what I understand, the photons create wave-like vibrations in the crystalline structure that carry the electron and shift its momentum towards the conduction band? If so, how does a photon achieve that?

Qmechanic
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Pre-alpha
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1 Answers1

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In electron transitions due to light absorption/emission in an indirect band-gap semiconductor usually phonons provide the missing momentum to ensure momentum conservation. This is necessary because photons have a large energy but a comparatively small momentum.

freecharly
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