利用光纤锥耦合的方法来激发光纤微柱腔中的光学回音壁模式,从而获得光纤微柱腔的传输谱线.主要研究了光纤锥的耦合位置以及输入激光的偏振态对光纤微柱腔传输谱线的影响.实验结果表明:当光纤锥垂直放置在距离光纤微柱腔切平端较远处时可以得到较高的品质因子,但耦合位置的改变对被有效激发的模式的共振波长基本没有影响;当改变输入激光的偏振态时,被激发的回音壁模式的共振波长会有些不同,但其Q值基本不变.
We use a fiber taper to excite whispering gallery modes of a fiber microcylinder to obtain the transmission spectra. The influences due to the distance of the fiber taper to the end of the microcylinder and the polarization of the input light on the transmission spectra are experimentally investigated. It is shown that a much higher Q value will be obtained when the fiber taper is kept vertical to the microcylinder and placed far away from the end of the microcylinder,but the position of the fiber taper has little effect on the resonance wavelength of excited modes. It is also shown that the resonance wavelengths of the excited whispering gallery modes will have some difference when the polarization of the input light are different,but the Q factors are almost the same.