Mach-Zehnder interferometer using frequency-domain beamsplitter

摘要

We demonstrated the first-order interference between coherent light at 1580nm and 795 nm by using frequency-domain Mach-Zehnder interferometer (MZI). TheMZI is implemented by two frequency-domain BSs based on a second-ordernonlinear optical effect in a periodically-poled lithium niobate waveguide witha strong pump light. We achieved the visibility of over 0.99 at 50% conversionefficiencies of the BSs. Toward photonic quantum information processing,sufficiently small background photon rate is necessary. From the measurementresults with a superconducting single photon detector, we discuss thefeasibility of the frequency-domain MZI in a quantum regime. Our estimationshows that single photon interference with the visibility above 0.9 is feasiblewith practical settings.