论文标题
由磁场快速变化驱动的电子旋转动力学的光学检测：测量$ t_1 $，$ t_2 $和$ t_2^*$的简单方法
Optical detection of electron spin dynamics driven by fast variations of a magnetic field: a simple method to measure $T_1$, $T_2$, and $T_2^*$ in semiconductors
论文作者
论文摘要
我们开发了一种简单的方法，用于测量电子旋转放松时间$ t_1 $，$ t_2 $和$ t_2^*$在半导体中，并将其模范应用显示为$ n $ type gaas。使用作用在电子自旋上的磁场的突然变化，我们通过测量短激光脉冲的法拉第旋转来检测自旋演变。根据磁场的定位，这使我们能够测量纵向自旋放松时间$ T_1 $或不均匀的横向自旋倾向时间$ T_2^*$。为了确定均匀的自旋相干时间$ t_2 $，我们将振荡辐射射频（RF）场的脉冲具有larmor频率的谐振，并检测到旋转进动的后续衰减。沿着磁场的其他光学泵送后，RF驱动的自旋进液的幅度显着增强。
We develop a simple method for measuring the electron spin relaxation times $T_1$, $T_2$ and $T_2^*$ in semiconductors and demonstrate its exemplary application to $n$-type GaAs. Using an abrupt variation of the magnetic field acting on electron spins, we detect the spin evolution by measuring the Faraday rotation of a short laser pulse. Depending on the magnetic field orientation, this allows us to measure either the longitudinal spin relaxation time $T_1$ or the inhomogeneous transverse spin dephasing time $T_2^*$. In order to determine the homogeneous spin coherence time $T_2$, we apply a pulse of an oscillating radiofrequency (rf) field resonant with the Larmor frequency and detect the subsequent decay of the spin precession. The amplitude of the rf-driven spin precession is significantly enhanced upon additional optical pumping along the magnetic field.
