On-Chip Weak Value Amplification
Optical interferometry has been a significant part of sensing and metrology. From gyroscope and surface examination to gravitational wave detection, optical interferometers are widely used for precision measurements. Weak value amplification is a technique that allows interferometric signal enhancement without amplifying technical noises. We implement weak value amplification on an integrated Mach-Zehnder interferometer by spatial and temporal phase engineering of the optical wave in waveguides. We achieve 7 dB signal-to-noise ratio improvement over standard integrated Mach-Zehnder interferometer (equal detected optical power) in a heat-induced phase shift measurement. Also, by adding ring resonator to the weak value interferometer as dispersive element, we detect an optical frequency shift down to 2 kHz.