Electron phenomena in layered conductors

TL;DR

This paper explores the unique electron and phonon phenomena in layered conductors, focusing on their magnetic field responses, oscillatory effects, and how point contact spectroscopy reveals detailed information about their electronic and vibrational spectra.

Contribution

It provides new insights into the magnetoresistance, electromagnetic, and acoustic wave propagation in layered conductors, highlighting the role of Fermi surface geometry and point contact spectroscopy in studying their electron and phonon spectra.

Findings

Magnetoresistance increases proportionally with magnetic field in layered conductors.

Electromagnetic and sound wave propagation depends on polarization relative to layers.

Point contact spectra are highly sensitive to magnetic field orientation, revealing Fermi surface details.

Abstract

The quasi-two-dimensional nature of the charge carriers energy spectrum in layered conductors leads to specific effects in an external magnetic field. The magnetoresistance of layered conductors in a wide range of strong magnetic fields directed in the plane of the layers can increase proportionally to a magnetic field value. The electromagnetic impedance and the sound attenuation rate depend essentially on the polarization of normal to the layers. Propagation of electromagnetic and acoustic waves in these conductors involves virtually all charge carriers in the transfer of acoustic pulses and electromagnetic field spikes to the bulk of the conductor. The orbits of Fermi electrons in a magnetic field are virtually indistinguishable, which allows the inclusion of large number of conduction electrons in the formation of peculiar oscillatory and resonant effects which are absent in the case of ordinary metals. Investigation of these effects introduce the possibilities for detailed study of the dissipative processes in electron systems of layered conductors and the charge carriers energy spectrum. Point contact investigations of layered metals allow us to obtain the information about electron and phonon spectra. The electron focusing signal and the point contact spectrum are extremely sensitive to the orientation of the magnetic field vector $\bs{H}$ in relation to the layers with a high electrical conductivity. The values of $\bs{H}$ for which the electron focusing signal has peaks can be used for determining velocities and extremal diameters for the open Fermi surface. The dependence of the point contact spectra on the magnitude and the relaxation of electrons at various types of phonon excitations.