Interferometric measurement with external modulation and recycling: theory and verification

A novel modulation technique for the shot-noise-limited measurement of the different displacement between arms of a Michelson interferometer is presented. Electrooptic modulation is applied to a reference beam external to the Michelson system, avoiding modulator-induced losses and wavefront distortions and allowing efficient power increase through recycled-light operation. Results for initial proof-of-concept experiments are given and show reasonable agreement with theory. >