Near 100％ spectral-purity photons from reconfigurable micro-rings

• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2020,（11）
• 所属期刊栏目: RAPID COMMUNICATION
• 页码范围: 135-139
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/1674-1056/abbb28

摘要

We propose an on-chip reconfigurable micro-ring to engineer the spectral-purity of photons.The micro-ring resonator is designed to be coupled by one or two asymmetric Mach-Zehnder interferometers and the coupling coefficients hence the quality-factors of the pump and the converted photons can be dynamically changed by the interferometer's internal phase-shifter.We calculate the joint-spectrum function and obtain the spectral-purity of photons and Schmidt number under different phases.We show that it is a dynamical method to adjust the spectral-purity and can optimize the spectral-purity of photons up to near 100％.The condition for high-spectral-purity photons is ensured by the micro-ring itself,so it overcomes the trade-off between spectral purity and brightness in the traditional post-filtering method.This scheme is robust to fabrication variations and can be successfully applied in different fabrication labs and different materials.Such high-spectral-purity photons will be beneficial for quantum information processing like Boson sampling and other quantum algorithms.