Generating entangled two-photon states with coincident frequencies.
It is shown that parametric down-conversion, with a short-duration pump pulse and a long nonlinear crystal that is appropriately phase matched, can produce a frequency-entangled biphoton state whose individual photons are coincident in frequency. Quantum interference experiments which distinguish this state from the familiar time-coincident biphoton state are described.
Giovannetti
Vittorio
V
Massachusetts Institute of Technology, Research Laboratory of Electronics, Cambridge, MA 02139, USA.
Maccone
Lorenzo
L
Shapiro
Jeffrey H
JH
Wong
Franco N C
FN