Whispering gallery modes with different polarizations in semiconductor microrod with rectangle shape

The whispering gallery modes (WGMs) of the ZnO photoluminescence emission were investigated in this paper. The transmission electron microscopy and X-ray diffraction results confirm that the rectangle microrod has a single crystalline wurtzite structure. Except for the band-edge emission, the visible luminescence band of the ZnO microrod presents the WGMs with two different polarizations. In a large waveband, the WGMs modes with two different polarizations have same mode spacing. Because of the phase difference in reflectance for two polarizations, the WGMs for s and p polarizations are distributed interlacedly. Due to the property difference, the WGMs for two polarizations have different appearances.