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 At such temperatures, the usual description of a metal in terms of ballistically propagating quasiparticles is no longer valid.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】

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