Quantum optical interference device has coupler in which both photons of photon pair interfere and leave either via different or same outputs, first and second photon detectors, coincidence circuit

摘要

The device has a photon source, an interferometer with optical delays in first and second arms and a beam coupler with two inputs and outputs. Both photons of a photon pair interfere in the coupler and leave via different or the same outputs. First and second detectors detect a photon or photons leaving by first or second outputs. A coincidence circuit trips a coincidence signal or anti-coincidence signal depending on which photons are detected. The device has a photon source (1), an interferometer with 2 arms, first and second optical delays (11,111) in the first and second arms and a beam coupler (30) with first and second inputs and outputs. Both photons of a photon pair interfere in the coupler and leave either via different or the same outputs. First and second detectors (33,133) detect a photon or photons leaving by first or second outputs and a coincidence circuit (40) trips a coincidence signal or anti-coincidence signal depending on which photons are detected. AN Independent claim is also included for the following: a method of operating an inventive device.