Accelerating photonic quantum information processing by a spectral modulation of photon pairs

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K14393
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 13020:Semiconductors, optical properties of condensed matter and atomic physics-related
• Research Institution: National Institute of Information and Communications Technology
• Principal Investigator: Tsujimoto Yoshiaki 国立研究開発法人情報通信研究機構, 未来ICT研究所量子ICT先端開発センター, 研究員 (80807470)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: 量子光学 / 量子情報 / 量子通信

Outline of Final Research Achievements

In this work, we developed a simple model to consider the influence of the repetition rate of the pump laser and timing jitter of the single photon detectors on the spectral purity, and experimentally demonstrated a high-visibility Hong-Ou-Mandel interference between two independent heralded single photons generated by spontaneous parametric down-conversion with 3.2 GHz-repetition-rate mode-locked pump pulses. The observed visibility of 0.88±0.03 is much higher than the classical limit of 0.5, and in good agreement with the theoretical value of 0.93.

Free Research Field

量子光学

Academic Significance and Societal Importance of the Research Achievements

自発的パラメトリック下方変換で生成した量子もつれ光子対は、量子通信の重要なリソースである一方で、高いクロックレートの励起レーザを用いて生成すると干渉性が劣化するという問題を抱えており、応用の幅が大きく制限されていた。本研究では、この問題を解決し、高い干渉性を有する量子もつれ光子対生成の超高速生成を実現した。