Abstract

We propose a method to simultaneously measure the center frequency of a spectral feature and the frequency linewidth of the feature. The method relies on dual frequency modulation of a carrier frequency, which probes the spectral feature, and phase sensitive detection of the transmitted signal at the two modulation frequencies. The detected signals provide two servo-stabilization signals for frequency control of the carrier frequency to the resonance line center and one of the modulation frequencies to the resonance linewidth.

© 2010 Optical Society of America

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