Neutron and Brillouin Scattering in Quantum Crystals

Abstract
Inelastic coherent neutron scattering and stimulated Brillouin scattering of light are discussed in the framework of first‐order self‐consistent theory of quantum crystals. The theory is applied to solid argon over the temperature range 4°–77°K and over a range of pressures from 0 to 200 atm. We show that anharmonic effects are substantial. Thermal expansion effects are identified and discussed separately. Our work is based on a (6–12) Lennard‐Jones potential with parameters fixed to the sublimation energy and lattice constant of Ar at 0°K.