Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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Simulation of Leggett-Garg Inequalities Using a Heralded-single-photon Source

예고된 단일 광자 광원을 이용한 레겟-가르그 부등식 모사

  • Kim, Su Hyun (Department of Physics, Pusan National University) ;
  • Moon, Han Seb (Department of Physics, Pusan National University)
  • Received : 2020.12.02
  • Accepted : 2020.12.16
  • Published : 2021.02.25
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Abstract

We have experimentally simulated the violation of the Leggett-Garg inequality (LGI) using a heralded-single-photon source via spontaneous parametric down-conversion (SPDC) in a periodically poled potassium titanyl phosphate (PPKTP) crystal. We measured the polarization fringe as a function of the angle of the linear polarization of the photons, and analyzed the LGI according to n measurement. Simulation results for LGI based on the polarization of the heralded single photon were in good agreement with theoretical calculations.

본 논문에서는 주기적 분극된 비선형 결정(periodically poled potassium titanyl phosphate; PPKTP)에서 자발매개하향변환(spontaneous parametric down conversion; SPDC)과정으로 생성된 예고된 단일 광자 광원을 이용하여 레겟-가르그 부등식(Leggett-Garg inequality; LGI)의 위배를 실험적으로 모사하였다. 생성된 광자의 편광 방향에 따라서 편광된 광자 수를 측정하여 n-측정수에 따른 레겟-가르그 부등식을 모사하였다. 단일 광자의 편광 기반 LGI에 대한 실험 결과는 이론적인 계산 결과와 일치하는 것을 확인하였다.

Keywords

Acknowledgement

이 연구는 부산대학교 기본연구지원사업(2년)에 의하여 수행되었음.

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