Lasing dynamics of a silicon photonic crystal microcavity

In this paper we propose a novel silicon microcavity design based on the dispersion engineered photonic crystals (PhCs). With the unique self-collimation property of PhCs, we optimize the passive cavity by tuning the design parameters, such as coupling gap size and array size, to achieve higher Q factor and drop efficiency. Highest cavity mode below the band edge is of particular interest. The strong mode confinement in the low index active material offers an opportunity to realize a lasing mechanism. To investigate the lasing dynamics we introduce the rate equations of atomic system into the electromagnetic polarization to fully describe the nonlinearity of active medium. With these auxiliary differential equations we solve the time evolutions of the electromagnetic waves and atomic populations by using the FDTD method.