High-purity single-photon source and its application in quantum information

Date/Time: Mon., 13th April 2015 15:00-16:00 - (room 1320 (3F), Science Building 4, Hongo-campus, University of Tokyo)

Speaker: Dr. Ruibo Jin (Quantum ICT Laboratory, National Institute of Information and Communications Technology)

Over the last several decades, quantum information science has become an attractive field in physics, and many experimental efforts have been devoted in order to demonstrate complicate quantum information protocols. For further development of this field, more sophisticated photon engineering and detection technologies are indispensable, but it is limited by the performance of conventional photon sources and detectors. In this talk, I will provide state-of-art technologies of our photon source and detectors in order to overcome such difficulties. This talk will include 6 parts. Part 1 is the introduction of the single photon source engineering techniques and superconducting nanowire single photon detector techniques. In part 2, I will introduce a spectrally pure single-photon source with widely tunability. This photon source is generated from parametric downcoversion process in a PPKTP crystal at telecom wavelengths. Prat 3 will discuss a quantum interference between two single-photon sources at telecom wavelength. In Part 4, the single photon source will be updated to an entangled photon source using a Sagnac-loop configuration. Part 5 will show the entanglement swapping and teleportation experiments with two entangled photon sources. Part 6 is the conclusion and outlook.