CONFINED ACOUSTIC PHONONS IN A FREESTANDING QUANTUM-WELL AND THEIR INTERACTION WITH ELECTRONS

The Lagrangian of an isotropic continuous medium and Lagrangian formal ism are used to consistently derive acoustic eigenmodes, to normalize them, and to determine the acoustic phonons (confined acoustic phonons ) in a free-standing quantum well. These phonons may be classified as shear, dilatational, and flexural phonons in accordance with the acous tic terminology for eigenmodes. The Hamiltonians describing interactio ns of the confined acoustic phonons with electrons in the approximatio ns of the deformation potential and the piezoelectric scattering poten tial are obtained and analyzed.