Electromagnetic quantum waves and their effect on the low temperature magnetoacoustic response of a quasi-two-dimensional metal

We theoretically analyze weakly attenuated electromagnetic waves in quasi-two-dimensional (Q2D) metals in high magnetic fields. Within the chosen geometry, the magnetic field is directed perpendicularly to the conducting layers of a Q2D conductor. We showed that longitudinal collective modes could propagate along the magnetic field provided that the Fermi surface is moderately corrugated. The considered waves speeds strongly depend on the magnetic field magnitude. Also, we analyzed interactions of these quantum waves with sound waves of fitting polarization and propagation direction, and we showed that such interaction may bring significant changes to the low temperature magnetoacoustic response of Q2D conductors.