论文标题
Terahertz辐射在HGTE量子孔中引起的影响电离
Impact ionization induced by terahertz radiation in HgTe quantum wells of critical thickness
论文作者
论文摘要
我们报告了Terahertz（THz）辐射诱导的带对波段撞击电离在\ HGTE量子井中（QW）结构的临界厚度的电离，其特征在于几乎线性的能量分散体。 THZ电场驱动载体初始化电子孔对的生成。在辐射角频率$ω$和动量松弛时间$τ_{\ text l} $大于统一的情况下，观察到的光子能量小于能量差距小于能量差距的载体乘积。在这种情况下，电荷载体仅由于存在高频电场的碰撞而获得高能量。开发的显微镜理论表明，光影电离的概率与$ \ exp（-e_0^2/e^2）$成正比，带有辐射电场振幅$ e $和特征场参数$ e_0 $。正如实验中观察到的那样，它表现出$ωτ\ gg 1 $的强频依赖性，其特征是特征场$ e_0 $线性地增加，随着辐射频率$ω$线性增长。
We report on the observation of terahertz (THz) radiation induced band-to-band impact ionization in \HgTe quantum well (QW) structures of critical thickness, which are characterized by a nearly linear energy dispersion. The THz electric field drives the carriers initializing electron-hole pair generation. The carrier multiplication is observed for photon energies less than the energy gap under the condition that the product of the radiation angular frequency $ω$ and momentum relaxation time $τ_{\text l}$ larger than unity. In this case, the charge carriers acquire high energies solely because of collisions in the presence of a high-frequency electric field. The developed microscopic theory shows that the probability of the light impact ionization is proportional to $\exp(-E_0^2/E^2)$, with the radiation electric field amplitude $E$ and the characteristic field parameter $E_0$. As observed in experiment, it exhibits a strong frequency dependence for $ωτ\gg 1$ characterized by the characteristic field $E_0$ linearly increasing with the radiation frequency $ω$.
