Polarization-modified Fano line shape spectrum with a single whispering gallery mode

Using the HE11X and HE11Y modes in a tapered fiber (TF) and the whispering gallery mode (WGM) in a microsphere resonator, Fano line-shape spectra were theoretically described and experimentally observed in this study. The line shapes of the spectra can be tuned to form a Lorentz notch, various Fano line shapes, and the Lorentz peak by controlling the polarizations at the input and output ports of the TF. The relative position or the size of the waveguide and WGM resonator do not need to be accurately controlled to produce these effects. The proposed configuration is suitable for mass production and will improve the performance of the devices in which it is applied.