Electron-longitudinal acoustic phonon interaction

The electron-longitudinal acoustic phonon interaction is an interaction that can take place between an electron and a longitudinal acoustic (LA) phonon in a material such as a semiconductor. == Displacement operator of the LA phonon == The equations of motion of the atoms of mass M which locates in the periodic lattice is M d 2 d t 2 u n = − k 0 ( u n − 1 + u n + 1 − 2 u n ) {\displaystyle M{\frac {d^{2}}{dt^{2}}}u_{n}=-k_{0}(u_{n-1}+u_{n+1}-2u_{n})} , where u n {\displaystyle u_{n}} is the displacement of the nth atom from their equilibrium positions.

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