  The annular photonic crystals have been regarded as a satisfactory candidate
to realize dual-polarization photonic device. In this letter, we focus our
attention on the study of annular photonic crystal cavity to verify its
application in light emission. We proposed a two-dimensional photonic crystal
model with annular air units and a point-line defect to construct a cavity for
the enhancement of light emission of InAs quantum dots. With the help of global
optimization method, we have obtained an annular photonic crystal cavity design
which can show a high in-plane quality factor of about 1.3*105 and 2.8*106 for
transverse electric and transverse magnetic polarizations, respectively. Based
on the Electron Beam Lithography and Reactive Ion Etching techniques, such
cavity pattern was transferred into the top of InAs/GaAs active layer. The
photoluminescence spectra of sample demonstrated clear light emission at around
1.3 um for both polarizations. Such dual-polarization light emitter has
potential applications in optical communications, quantum information
processing and other relative areas.
