Resonant Point Tracking and Locking Technique Based on Microsphere Resonator

Abstract:

Abstract. Microsphere resonator is widely studied for the high quality factor Q and small mode volume. Aimed at the sensor applications, the resonant point tracking and locking method is proposed for measuring the resonant frequency shift. To avoid external noises, such as air flow and vibration, spot-packaged coupling structure is adopted. The robustness of microsphere-taper coupling unit is greatly improved. And this lays a foundation for resonant point tracking and locking. By employing modulation method, the demodulation signal is obtained. To lock the laser frequency to resonant point, PID circuits will adjust the center frequency of laser until the intensity of demodulation signal becomes zero. In the experiment, resonant tracking and locking is realized on the rotating platform with rotation rate 2 r/s.

• Periodical: Key Engineering Materials (Volumes 562-565)
• Pages: 553-558
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.562-565.553
• Online since: July 2013
• Authors: Peng Fei Xu, Jian Hui Zhang, Ke Zhen Ma, Shu Bin Yan, Wen Dong Zhang
• Keywords: Locking, Microsphere Resonator, Modulation Method, Spot-Package, Tracking

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