arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 0707.3555cond-mat.mes-hall
收藏

半导体量子点中光电流线型的功率依赖性

Power Dependence of the Photocurrent Lineshape in a Semiconductor Quantum Dot

A. Russell, Vladimir I. Fal'ko

摘要:

提出了一个动力学理论来描述低温下光泵量子点中光电流(PC)线型的功率依赖性$I_{PC}(P)$,包括零磁场和有限磁场。我们发现,有一个交叉功率$P_c$,由电子和空穴隧穿率,在该光电流谱成为强烈的影响点动力学,并不再反映激子寿命的点。对于$P>P_c$,我们表明,光电流饱和,由于缓慢的空穴逃逸速率(例如,InGaAs/GaAs点),而线宽随功率增加:$Γ\propto \sqrt{P}$。我们还分析了在强磁场中所研究的光电流的自旋二重态线形如何反映入射光的圆偏振度。

英文摘要:

We propose a kinetic theory to describe the power dependence, $I_{PC}(P)$, of the photocurrent (PC) lineshape in optically pumped quantum dots at low temperatures, in both zero and finite magnetic fields. We show that there is a crossover power $P_c$, determined by the electron and hole tunneling rates, at which the photocurrent spectra become strongly influenced by the dot kinetics, and no longer reflect the exciton lifetime in the dot. For $P>P_c$, we show that the photocurrent saturates due to the slow hole escape rate (in e.g., InGaAs/GaAs dots), whereas the line-width increases with power: $Γ\propto \sqrt{P}$. We also analyze to what measure the spin-doublet lineshape of the photocurrent studied in a high magnetic field reflects the degree of circular polarization of the incident light.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑