Possible zero sound in layered perovskites with ferromagnetic s-d exchange interaction

Abstract

We analyze the conditions for observation of zero sound in layered perovskites with transition metal ion on chalcogenide oxidizer. We conclude that propagation of zero sound is possible only for a ferromagnetic sign of the s-d interaction. If the s-d exchange integral J_{sd} has antiferromagnetic sign, as it is perhaps in the case for layered cuprates, zero sound is a thermally activated dissipation mode, which generates only “hot spots” in the Angle Resolved Photoemission Spectroscopy (ARPES) data along the Fermi contour. We predict that zero sound will be observable for transition metal perovskites with 4s and 3d levels close to the p-level of the chalcogenide. The simultaneous lack of superconductivity, the appearance of hot spots in ARPES data, and the proximity of the three named levels, represents the significant hint for the choice of material to be investigated.