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Photonics provide an efficient way to implement quantum walks, the quantum analog of classical random walks, which demonstrate rich physics with potential applications. However, most photonic quantum walks do not involve photon interactions, which limits their potential to explore strongly correlated many-body physics of light. We propose a strongly interacting discrete-time photonic quantum walk using a network of single atom beamsplitters. We calculate output statistics of the quantum walk for the case of two photons, which reveals the strongly correlated transport of photons. Particularly, the walk can exhibit either bosonlike or fermionlike statistics which is tunable by postselecting the two-photon detection time interval. Also, the walk can sort different types of two-photon bound states into distinct pairs of output ports under certain conditions. These unique phenomena show that our quantum walk is an intriguing platform to explore strongly correlated quantum many-body states of light. Finally, we propose an experimental realization based on time-multiplexed synthetic dimensions.
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This content will become publicly available on August 1, 2026
Parity-dependent photon-subtracted two-mode squeezed vacuum states
The removal of photons from certain quantum light sources produces so-called photon-subtracted states with enhanced mean photon numbers and intricate quantum correlations. Here, we propose an integrated photon-subtraction scheme that, contrary to previous approaches, is not heralded by photon correlation (coincidence) measurements. In this way, our technique exploits the “Welcher Weg” (“which way”) information problem, as it does not provide information about the modes from which the subtracted photons emanated. We show that this lack of information allows the generation of multiphoton states endowed with rich quantum correlations that strongly depend on the parity, evenness or oddness, of the number of subtracted photons.
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- Award ID(s):
- 2328993
- PAR ID:
- 10639276
- Publisher / Repository:
- APS
- Date Published:
- Journal Name:
- Physical Review A
- Volume:
- 112
- Issue:
- 2
- ISSN:
- 2469-9926
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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