Mott-Ioffe-Regel limit and resistivity crossover in a tractable electron-phonon model | |
Article | |
关键词: SATURATION; METALS; SUPERCONDUCTIVITY; TRANSPORT; | |
DOI : 10.1103/PhysRevB.93.075109 | |
来源: SCIE |
【 摘 要 】
Many metals display resistivity saturation-a substantial decrease in the slope of the resistivity as a function of temperature that occurs when the electron scattering rate tau(-1) becomes comparable to the Fermi energy E-F/h (the Mott-Ioffe-Regel limit). At such temperatures, the usual description of a metal in terms of ballistically propagating quasiparticles is no longer valid. We present a tractable model of a large number N of electronic bands coupled to N-2 optical phonon modes, which displays a crossover behavior in the resistivity at temperatures where tau(-1) similar to E-F/h. At low temperatures, the resistivity obeys the familiar linear form, while at high temperatures, the resistivity still increases linearly, but with a modified slope (that can be either lower or higher than the low-temperature slope, depending on the band structure). The high-temperature non-Boltzmann regime is interpreted by considering the diffusion constant and the compressibility, both of which scale as the inverse square root of the temperature.
【 授权许可】
Free