Hiding the which-path information of photons

作者：Guo, Jinxian^*; Yuan, Qizhang; Wu, Yuan; Zhang, Weiping

来源：Physical Review A - Atomic, Molecular, and Optical Physics, 2022, 106(2): 022210.

DOI：10.1103/PhysRevA.106.022210

• DISCONNECTED TRAJECTORIES
• WEAK MEASUREMENTS
• QUANTUM
• COMPLEMENTARITY
• PARADOX

Which-path information of a quantum particle in interferometers is the key to infer the past of the quantum particle. It has led to many extensive discussions, including discussions of quantum complementarity and the path-visibility relation. The basics of these discussions are the description, detection, and control of which -path information. In this paper, we focus on the investigation of multidimensional which-path information in a nested Mach-Zehnder interferometer. A general expression of which-path information is given and can be partially extracted by different detection methods. Further analysis shows that the which-path information can be controlled by the phase differences and beam-splitting ratios between the arms of the nested Mach-Zehnder interferometer. Moreover, an alternative which-path information elimination phenomenon has been predicted and demonstrated experimentally. Our work can help us to understand the physics of quantum particles, with potential applications for quantum information processing and quantum metrology.

• 单位
  上海交通大学