Non-local quantum interference controlled by an undetected photon and integrated photonics for quantum network

Quantum technology employs the ‘spooky’ phenomena of quantum physics such as superposition, randomness and entanglement to process information in a novel way. Quantum optics provides a promising path for both delivering quantum-enhanced technologies and exploring fundamental physics.

In the first part of this talk, I will introduce our recent work on multiphoton non-local quantum interference controlled by an undetected photon [1], in which we demonstrate multiphoton non-local quantum interference that does not require entanglement of any intrinsic properties of the photons. With the intrinsic indistinguishability in the generation process of photons, we realize four-photon frustrated quantum interference. This allows us to observe the noteworthy difference to quantum entanglement: We control the non-local multipartite quantum interference with a photon that we never detect, which does not require quantum entanglement.

In the second part of my talk, I will present our recent endeavors in developing functional nodes for quantum information processing based on integrated optics architecture and their potential applications in a metropolitan fiber network.

They include:

1. Heterogeneously integrated, superconducting silicon-photonic chip for quantum key distribution [2];

2. Solid-state quantum memory at telecom wavelength [3].

3. Generation and manipulation of multiphoton entangled states [4].

References:

1. Qian, K. et al. Multiphoton non-local quantum interference controlled by an undetected photon. Nat Commun14, 1480 (2023).

2. Zheng, X. et al. Heterogeneously integrated, superconducting silicon-photonic platform for measurement-device-independent quantum key distribution. Adv Photonics3, 055002–055002 (2021).

3. Ming-Hao Jiang, Wenyi Xue, Qian He, Yu-Yang An, Xiaodong Zheng, Wen-Jie Xu, Wenjun Wen, Yu-Bo Xie, Yanqing Lu, Shining Zhu, Xiao-Song Ma. Quantum storage of entangled photons at telecom wavelengths in a crystal. https://arxiv.org/abs/2212.12898.

4. Chen, L. et al. On-Chip Generation and Collectively Coherent Control of the Superposition of the Whole Family of Dicke States. Phys. Rev. Lett.130, 223601 (2023).