A novel scheme employing two pulses separated by a short time delay is used to cancel the phase noise from guided-acoustic-wave Brillouin scattering in a fiber ring interferometer. The dual-pulse-excited fiber ring is used to generate squeezed vacuum that, when injected into a measuring Mach-Zehnder interferometer, improves its sensitivity by 3 dB beyond the shot-noise limit.
© 1993 Optical Society of America
K. Bergman, C. R. Doerr, H. A. Haus, and M. Shirasaki, "Sub-shot-noise measurement with fiber-squeezed optical pulses," Opt. Lett. 18, 643-645 (1993)