Density matrix model for polarons in a terahertz quantum dot cascade laser

Article

关键词: ANHARMONIC DECAY;    ELECTRON-TRANSPORT;    PHONON BOTTLENECK;    RELAXATION;    LIFETIME;    ENERGY;   

DOI  :  10.1103/PhysRevB.90.155309

来源: SCIE

【 摘 要 】

A density matrix based method is introduced for computation of steady-state dynamics in quantum cascade systems of arbitrary size, which incorporates an optical field coherently. The method is applied to a model terahertz quantum dot cascade laser system, where a means of treating coherent electron-optical-phonon coupling is also introduced. Results predict a strong increase in the upper state lifetime and operating temperature as compared to traditional well-based terahertz quantum cascade lasers. However, new complications also arise, including multiple peaks in the gain spectrum due to strong electron-phonon coupling, and strong parasitic subthreshold current channels that arise due to reduced dephasing. It is anticipated that novel design schemes will be necessary for such lasers to become a reality.

【 授权许可】

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