Time-bin entangled photon pairs from spontaneous parametric down-conversion pumped by a cw multi-mode diode laser

摘要: Generation of time-bin entangled photon pairs requires the use Franson interferometer which consists two spatially separated unbalanced Mach-Zehnder interferometers through signal and idler photons from spontaneous parametric down-conversion (SPDC) are made to transmit individually. There have been SPDC pumping regimes where scheme works: narrowband regime double-pulse regime. In regime, process is pumped by a cw laser with coherence length much longer than path difference interferometer. longitudinal separation between pulse pair equal this paper, we propose another generation entanglement possible demonstrate experimentally. our scheme, differently previous approaches, multi-mode (i.e., short length) makes revival property such laser. The high-visibility two-photon interference demonstrates clearly that high-quality source can be developed using inexpensive diode lasers for various quantum communication applications.