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arXiv · 2608.03658

Bimodal non-Gaussian photonic states from a single quantum emitter in a waveguide

Thomas Copie·Ofer Firstenberg·G. P. Teja·Radim Filip·Hanna Le Jeannic
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Abstract

We investigate the generation of deterministic and heralded non-Gaussian states of light, using a single two-level system coupled to a chiral waveguide. We study the case of a single two level system driven by pulsed coherent and squeezed drive in a chiral waveguide. For coherent input pulses, we show that the emitter can deterministically generate Wigner-negative states, albeit of limited rank. Going beyond, using squeezed-vacuum inputs, we show that the interaction produces bimodal non-Gaussian states from which higher-stellar-rank states, including large squeezed cat states, can be experimentally extracted with a substantial success rate. Motivated by experimental implementations, we further analyze the effect of imperfect coupling and of the intrinsic $50\%$ collection limit of symmetric, non-chiral waveguides. Finally, we propose a simple interferometric scheme that recovers an effectively chiral interaction in an otherwise bidirectional waveguide.

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Thomas Copie, Ofer Firstenberg, G. P. Teja, Radim Filip, Hanna Le Jeannic. 2026-08-04. Bimodal non-Gaussian photonic states from a single quantum emitter in a waveguide. https://arxiv.org/abs/2608.03658

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