Analytical model of spin-polarized semiconductor lasers

We formulate an analytical model for semiconductor lasers with injection (pump) of spin-polarized electrons, allowing us to systematically investigate different operating regimes. We demonstrate that the maximum threshold reduction by electrically pumped spin-polarized carriers is larger than previously thought possible and, surprisingly, can be enhanced by ultrafast spin relaxation of holes. We reveal how different modes of carrier recombination directly affect the threshold reduction. Neither spin-up nor spin-down electron populations are separately clamped (pinned) near the threshold, where such lasers can act as effective nonlinear filters of circularly polarized light, owing to their spin-dependent gain. (C) 2008 American Institute of Physics.