andrew jordanCo-director of the Institute for Quantum Studies Dr. Andrew Jordan’s theory of weak value amplification with waveguides inspired a breakthrough in the development of a device that is a more sensitive, robust and compact platform for measuring optical phase. In partnership with researchers from the Institute of Optics at the University of Rochester, the device was engineered to include a waveguide to propagate the wavefront of an optical field through a 1 mm by 1 mm integrated photonic chip. This new development outlined in Nature Communications will play a key role in precision metrology such as frequency measurements, gyroscopes and environmental sensing, and can be adapted to the quantum domain. 

They implemented a generalized form of Jordan’s theory of weak value amplification on a compact on-chip silicon nitride photonic platform with a multi-mode interferometer. Doing so, they were able to engineer an on-chip phase front tilt with tapered waveguides and multimode interference structures in order to achieve post-selection. 

Their device showed 7dB of signal enhancement over a standard Mach-Zehnder interferometer. 

“This invention brings the advantages of weak value amplification to integrated optics.  The robust platform of the monolithic chip both miniaturizes the sensor and allows it to be used in everyday applications,” shared Jordan. 

This discovery opens applications of weak value amplification to other fields in integrated photonics, such as coherent communications and quantum applications, where phase measurements are crucial. Moving forward the researchers will work to adapt the device using squeezed or entangled photons to enable devices such as quantum gyroscopes. 

This work was supported by Leonardo DRS and A. N. Jordan Scientific, LLC. 

Cover photo: (To the left) Magenta lines indicate the waveguide design directing the light through the chip. Purple lines represent in a different layer, heaters can control the optical phase via a thermo-optical control of the index of refraction. (To the right) Experimental layout. Laser light is fiber-coupled into the chip.



Nature Communications




Theory and experiment


Integrated optical interferometers, and precision measurements of optical frequency using weak-value inspired techniques


“Enhanced on-chip phase measurement by inverse weak value amplification”