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Title: Temporal trapping: a route to strong coupling and deterministic optical quantum computation

The realization of deterministic photon–photon gates is a central goal in optical quantum computation and engineering. A longstanding challenge is that optical nonlinearities in scalable, room-temperature material platforms are too weak to achieve the required strong coupling, due to the critical loss-confinement trade-off in existing photonic structures. In this work, we introduce a spatio-temporal confinement method, dispersion-engineered temporal trapping, to circumvent the trade-off, enabling a route to all-optical strong coupling. Temporal confinement is imposed by an auxiliary trap pulse via cross-phase modulation, which, combined with the spatial confinement of a waveguide, creates a “flying cavity” that enhances the nonlinear interaction strength by at least an order of magnitude. Numerical simulations confirm that temporal trapping confines the multimode nonlinear dynamics to a single-mode subspace, enabling high-fidelity deterministic quantum gate operations. With realistic dispersion engineering and loss figures, we show that temporally trapped ultrashort pulses could achieve strong coupling on near-term nonlinear nanophotonic platforms. Our results highlight the potential of ultrafast nonlinear optics to become the first scalable, high-bandwidth, and room-temperature platform that achieves strong coupling, opening a path to quantum computing, simulation, and light sources.

 
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Award ID(s):
1918549 2011363
PAR ID:
10380442
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optica
Volume:
9
Issue:
11
ISSN:
2334-2536
Format(s):
Medium: X Size: Article No. 1289
Size(s):
Article No. 1289
Sponsoring Org:
National Science Foundation
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