We investigate coherent and squeezed quantum states of phonons. The latter allow the possibility of modulating the quantum fluctuations of atomic displacements below the zero-point quantum noise level of coherent states. The expectation values and quantum fluctuations of both the atomic displacement and the lattice amplitude operators are calculated in these states—in some cases analytically. We also study the possibility of squeezing quantum noise in the atomic displacement using a polariton-based approach. © 1996 The American Physical Society.
- Received 27 September 1995
- Published in the issue dated 1 February 1996
© 1996 The American Physical Society