Polariton parametric scattering processes in semiconductor microcavities observed in continuous wave experiments
Polariton parametric scattering processes in semiconductor microcavities observed in continuous wave experiments
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连续波实验中观察到的半导体微腔极化子参量散射过程
DOI：
10.1103/physrevb.65.081308
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发表时间：
2002
影响因子：
3.7
通讯作者：
J. Roberts
中科院分区：
文献类型：
--
作者：
A. Tartakovskii;D. Krizhanovskii;D. Kurysh;V. Kulakovskii;M. S. Skolnick;J. Roberts
研究了III-V半导体微腔中低极化激子(LP)分支拐点附近连续波共振激发下的新的极化激元-极化激元散射过程。除了由于Lp色散上激发点的参数极化散射而在k=0和2kP附近的波矢处产生强发射外，还在k=3kP和-kP附近观察到位于Lp支外的尖锐峰。我们证明了它们是由于宏填充k0、kP和2kP模之间的附加参数散射而产生的。在k=3kP附近发现了明显的峰的反常色散，并表明它起源于k=2kP附近宏观占据态的色散。在椭圆偏振激光激发下，观察到k3kP峰的偏振度高得惊人，明显超过激发时的偏振度。考虑到k3kP峰值发射在阈值附近的强非线性，对此进行了解释。我们还讨论了在高激发功率或高于15K的温度下，系统中的非相干过程对附加模布居的影响。
Novel polariton-polariton scattering processes in a III-V semiconductor microcavity are investigated under conditions of cw resonant excitation close to the point of inflection of the low polariton (LP) branch at wave vector k P . In addition to the strong emission at wave vectors near k=0 and 2k P occurring due to parametric polariton scattering from the excitation point on the LP dispersion, sharp peaks located off the LP branch are observed in the vicinity of k=3k P and -k P . We demonstrate that they arise due to additional parametric scattering between the macrofilled k0, k P and 2k P modes. Pronounced anomalous dispersion of the peak near k=3k P is found and shown to originate from that of the macroscopically occupied states near k=2k P . A surprisingly high degree of polarization of the k3k P peak, markedly exceeding that of the excitation, is observed under excitation with elliptically polarized laser light. It is explained taking into account strong nonlinearity of the k 3k P peak emission close to the threshold. We also discuss the effect of the incoherent processes in the system, occurring at high excitation power or at temperatures above 15 K, on population of the additional modes.