Consider a one-dimensional chain of identical atoms. The springs between them alternate in strength between values...

Consider a one-dimensional chain of identical atoms. The springs between them alternate in strength between values K1 and K2.

a) Find the vibrational frequencies as a function of wave number q. Study the low q limit and find the sound velocity.

b) Discuss the physical meaning of the two branches. Sketch the way the atoms move in both cases!

c) Discuss the dispersion and the normal modes for K1 ≫ K2.

Expert Solution

genius_generous answered 1 year ago

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