Crystal momentum

In solid-state physics crystal momentum or quasimomentum is a momentum-like vector associated with electrons in a crystal lattice. It is defined by the associated wave vectors ${\displaystyle \mathbf {k} }$ of this lattice, according to

(where ${\displaystyle \hbar }$ is the reduced Planck's constant). Like mechanical momentum, crystal momentum is frequently conserved, making it useful to physicists and materials scientists as an analytical tool.

A common method of modeling crystal structure and behavior is to view electrons as quantum mechanical particles traveling through a fixed infinite periodic potential ${\displaystyle V(x)}$ such that

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