Single-Ion Two-Photon Source
François Dubin, D. Rotter, Manas Mukherjee, S. Gerber, R. Blatt · Physical Review Letters · 2007
A single trapped ion is converted into a pseudo-two-photon source by splitting its resonance fluorescence, delaying part of it and by recombining both parts on a beam splitter. A destructive two-photon interference is observed with a contrast reaching 83(5)%. The spectral brightness of our two-photon source is quantified and shown to be comparable to parametric down-conversion devices.