arXiv subjects

Lee Drori

Publications and source records attributed to Lee Drori.

3 recordsLinked to original sources

arXiv2025

Long-Range Blockade Between Counter-Propagating Photons

Realizing strong interactions between individual photons, mediated by matter, is a cornerstone for advancing photonic quantum computing and quantum nonlinear optics. In such systems, the interaction range is typically limited by the narrow bandwidth of the material excitation, resulting in a tradeoff between interaction strength and pulse duration. Here, we address this limitation by exploring interactions between counter-propagating photons mediated by Rydberg polaritons. We experimentally demonstrate strong photon-photon interactions, achieving a record-long anti-correlation range exceeding $1~\mu s$. This extended range enables photon pulses that are long enough to fit within the polariton bandwidth, yet short enough to remain within the interaction range. Under these conditions, we observe complete photon blockade of entire pulses, tunable via their relative timing. Extending to the three-photon regime, we observe enhanced interactions when a photon encounters a counter-propagating pair. These results, supported by analytical theory and numerical simulations, establish counter-propagating Rydberg polaritons as a powerful platform for engineering interactions in quantum light fields, enabling deterministic photonic operations and opening new directions in few-photon quantum dynamics.

quant-ph↗

arXiv2025

Multiband dispersion and warped vortices of strongly-interacting photons

We present a theoretical study of quantum correlations between interacting photons realized through co-propagating Rydberg polaritons. We show that the spatial evolution of the $n$-photon wavefunction is governed by a multiband dispersion featuring one massive mode and multiple massless modes with degenerate Dirac points and $n$-fold rotational symmetry. The resulting band structure is warped, departing from the single-band, parabolic approximation commonly assumed for interacting polaritons. Our analytical results are supported by rigorous numerical modeling that fully accounts for photon propagation inside the finite atomic medium. These findings advance the understanding of multi-photon interactions and support the development of future multi-photon control tools.

quant-ph↗

arXiv2023

Quantum vortices of strongly interacting photons

Vortices are a hallmark of topologically nontrivial dynamics in nonlinear physics and arise in a huge variety of systems, from space and atmosphere to condensed matter and quantum gases. In optics, vortices manifest as phase twists of the electromagnetic field, commonly formed by the interaction of light and matter. Formation of vortices by effective interaction of light with itself requires strong optical nonlinearity and has therefore been confined, until now, to the classical regime. Here we report on the realization of quantum vortices resulting from a strong photon-photon interaction in a quantum nonlinear optical medium. The interaction causes faster phase accumulation for co-propagating photons. Similarly to a plate pushing water, the local phase accumulation produces a quantum vortex-antivortex pair within the two-photon wavefunction. For three photons, the formation of vortex lines and a central vortex ring attests to a genuine three-photon interaction. The wavefunction topology, governed by two- and three-photon bound states, imposes a conditional phase shift of $\pi$-per-photon, a potential resource for deterministic quantum logic operations.

quant-ph↗