The lab of Hong Tang, Llewellyn West Jones, Jr. Professor of Electrical Engineering & Physics, has developed a device that converts visible light to infrared light, a crucial step in building practical quantum information technology. The results of their work were published recently in Physical Review Letters.
Built on a chip, the wavelength converter would allow for the manipulation of quantum bits and the transmission of that same information over long distances.
Ref: On-Chip Strong Coupling and Efficient Frequency Conversion between Telecom and Visible Optical Modes. Physical Review Letters (16 September 2016) | DOI: 10.1103/PhysRevLett.117.123902
While the frequency conversion of photons has been realized with various approaches, the realization of strong coupling between optical modes of different colors has never been reported. Here, we present an experimental demonstration of strong coupling between telecom (1550 nm) and visible (775 nm) optical modes on an aluminum nitride photonic chip. The nonreciprocal normal-mode splitting is demonstrated as a result of the coherent interference between photons with different colors. Furthermore, a wideband, bidirectional frequency conversion with 0.14 on-chip conversion efficiency and a bandwidth up to 1.2 GHz is demonstrated.