标题： 能量依赖的二维电子气中的电子-电子散射和自旋动力学 显示英文标题

标题： Energy-Dependent Electron-Electron Scattering and Spin Dynamics in a Two Dimensional Electron Gas

摘要： 电子在简并二维电子气中的自旋动力学测量，其中Dyakonov-Perel机制占主导地位，已被用于研究接近费米能级处的电子散射时间(tp*)随能量的变化情况。 接近费米能级时，自旋演化是振荡的，表明自旋动力学处于准无碰撞区域。 当能量增加时，会发生向指数型、碰撞主导的自旋衰减的转变。 使用蒙特卡罗模拟方法提取频率和tp*的值。 在费米能级处，tp*非常接近通过电子迁移率得到的集体动量弛豫时间(tp)。 对于较高能量，tp*呈二次下降，这与电子-电子散射开始的理论预期一致，而在费米能级处电子-电子散射受到泡利原理的抑制。 显示英文摘要

摘要： Measurements of spin dynamics of electrons in a degenerate two dimensional electron gas, where the Dyakonov-Perel mechanism is dominant, have been used to investigate the electron scattering time (tp*) as a function of energy near the Fermi energy. Close to the Fermi energy the spin evolution is oscillatory, indicating a quasi-collision-free regime of spin dynamics. As the energy is increased a transition to exponential, collision-dominated, spin decay occurs. The frequency and the value of tp* are extracted using a Monte Carlo simulation method. At the Fermi energy tp* is very close to the ensemble momentum relaxation time (tp) obtained from the electron mobility. For higher energies tp* falls quadratically, consistent with theoretical expectations for the onset of electron-electron scattering which is inhibited by the Pauli principle at the Fermi energy.