论文标题
电子电子碰撞在中等温度下的磁转移的作用
The role of electron-electron collisions for magnetotransport at intermediate temperatures
论文作者
论文摘要
我们讨论了集中在中等温度上的无序电子系统中的电磁和热磁效应，电子电子散射和电子障碍散射以相似的速率发生，而与声子相关的效果则可以忽略。特别是，我们探讨了如何由电场或温度梯度驱动的电流和热电流如何受到动量依赖性电子脉冲散射，电子电子散射以及磁场的存在的影响。我们发现电阻，塞贝克系数和NERNST系数特别敏感，对中等温度下电子突发性散射速率的动量依赖性。电子突发性散射率的足够强大的动量依赖性可以引起Seebeck系数的符号变化。垂直磁场可以抑制这种标志变化。 Seebeck系数的温度和磁场依赖性可用于测量电子功能障碍和电子电子散射速率的大小。一旦考虑到动量依赖性，NERNST系数消失了动量独立的电子突发性散射，但在有限温度下显示出最大的依赖性。相比之下，HALL系数和Righi-LeDuc系数仅显示出对中等温度上电子突发性散射的动量依赖性的弱依赖性。
We discuss galvanomagnetic and thermomagnetic effects in disordered electronic systems focusing on intermediate temperatures, for which electron-electron scattering and electron-impurity scattering occur at similar rates, while phonon-related effects can be neglected. In particular, we explore how electric and thermal currents driven either by an electric field or by a temperature gradient are affected by the interplay of momentum-dependent electron-impurity scattering, electron-electron scattering, and the presence of a magnetic field. We find that the electric resistance, the Seebeck coefficient and the Nernst coefficient are particularly sensitive to the momentum dependence of the electron-impurity scattering rate at intermediate temperatures. A sufficiently strong momentum dependence of the electron-impurity scattering rate can induce a sign change of the Seebeck coefficient. This sign change can be suppressed by a perpendicular magnetic field. The temperature and magnetic field dependence of the Seebeck coefficient can be used for measuring the magnitude of the electron-impurity and electron-electron scattering rates. The Nernst coefficient vanishes for momentum-independent electron-impurity scattering, but displays a maximum at finite temperatures once the momentum dependence is accounted for. By contrast, the Hall coefficient and the Righi-Leduc coefficient display only a weak dependence on the momentum dependence of the electron-impurity scattering at intermediate temperatures.
