Consider a one-dimensional lattice with a basis of two non-equivalent atoms of masses M_1and M_2. 1....

Consider a one-dimensional lattice with a basis of two non-equivalent atoms of masses M_1and M_2.

1. Find the dispersion relations (ω versus k).

2. Sketch the normal modes in the first Brillouin zone.

3. Show that the ratio of the displacements of the two atoms u/v for the k = 0 optical mode is given by:u/v=-M_2/M_1

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genius_generous answered 1 year ago

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