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.

Fig 1. Schematic of integrated weak value interferometer for heat-induced phase measurement [1].