Unbalanced Fiber Optic Interferometer Research Articles

Method for Measuring Laser Frequency Noise

We have analyzed the characteristic features and problems in the major approaches to measurement of laser frequency noise. We propose a method in which we use an unbalanced fiber-optic interferometer, generation at the optical system output of a signal for a subcarrier of the frequency, phase-modulated by fluctuations in the laser frequency, and measurement of the spectrum for this signal. The proposed approach is distinguished by relative simplicity and accessibility, and does not require using uncommon specialized instruments and complicated specific procedures.

Phase noise characteristics of a diode-pumped Nd:YAG laser in an unbalanced fiber-optic interferometer

The measurement sensitivity of interferometric fiber sensors can be limited by the laser phase noise. We investigate the phase noise characteristics of a diode-pumped Nd:YAG laser in an unbalanced fiber-optic interferometer. Measurements were made of the phase-induced intensity noise of an interferometer with varying optical path differences. The experimental results of the relation between the noise and the optical path difference are given, and the application of the results in the design of a fiber-optic accelerometer is discussed.