2013 Fiscal Year Final Research Report

Experimental Demonstration of Quantum Metrology using Continuous-Wave Laser

Research Project

Project/Area Number	24740275
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Atomic/Molecular/Quantum electronics
Research Institution	Tokyo Women's Medical University
Principal Investigator	TSUJINO Kenji 東京女子医科大学, 医学部, 助教 (40415849)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	量子情報 / 量子計量学 / 量子光学
Research Abstract	Using the NOON state and a photon-number-resolving detector, the accuracy of phase measurement with a Mach–Zehnder interferometer reached the Heisenberg limit. In an experimental demonstration using the continuous-wave NOON state, the coherence time was much longer than the response time of a photon-number-resolving detector. Therefore, we investigated the time correlation of photon detection events in the light field from the Mach–Zehnder interferometer. As a result, it was found that the photon detection events were anti-bunching. This result suggests that we need a photon-number-resolving detector with a fast response time and a NOON state with a much longer coherence time in order to use a large-photon-number NOON state.