论文标题
强场激发固体中的瞬态光学增益
Transient optical gain in strong-field-excited solids
论文作者
论文摘要
通过几个周期的激光脉冲对固体激发的多光子激发形成了非常非平衡的电荷载体分布，在这种情况下，占用概率不一定会随着能量而降低。我们表明，在某些条件下，可以在数值或传导波段状态之间出现大量的种群反演，其中Bloch状态之间的过渡被偶极子。这种种群反转导致在不受干扰的固体是透明的频率下激光兴奋的固体中刺激的发射。我们建立了观察强场诱导的光学增益的最佳条件。
Multiphoton excitation of a solid by a few-cycle, intense laser pulse forms a very non-equilibrium distribution of charge carriers, where occupation probabilities do not necessarily decrease with energy. We show that, under certain conditions, significant population inversion can emerge between pairs of valence- or conduction-band states, where transitions between the Bloch states are dipole-allowed. This population inversion leads to stimulated emission in a laser-excited solid at frequencies where the unperturbed solid is transparent. We establish the optimal conditions for observing the strong-field-induced optical gain.
