We propose a scheme to realize nonreciprocal multiphoton bundle emission in a spinning resonator. The system consists of a rotating two-mode cavity directly coupled to a two-level atom, enabling efficient excitation of the desired multiphoton bundle states. These photon bundles originate from leapfrog transitions between dressed states, established through the coherent atom-cavity coupling under multiphoton resonance conditions. When the rotating resonator is driven in different directions, it generates opposite Sagnac-Fizeau shifts, making the resonant conditions dependent on the direction. As a consequence, distinct multiphoton transition channels can be selectively activated by tuning the driving direction and frequency. The nonreciprocal two-photon or three-photon bundle emission with the same and different modes can be implemented with a high tunability. This scheme provides a feasible route toward direction-controlled multiphoton emitters with potential applications in chiral quantum information processing.
Realizing precise control over multiquanta emission is crucial for quantum information processing, especially when integrated with advanced techniques of manipulating quantum states. Here, by spinning the resonator to induce the Sagnac effect, we can obtain nonreciprocal photon-phonon and photon-magnon super-Rabi oscillations under conditions of optically driving resonance transitions. Opening dissipative channels for such super-Rabi oscillations enables the realization of directional bundle emissions of entangled photon-phonon pairs and photon-magnon pairs by transferring the pure multiquanta state to a bundled multiquanta outside of the system. This nonreciprocal emission is a flexible switch that can be controlled with precision, and simultaneous emissions of different entangled pairs (such as photon-phonon or photon-magnon pairs) can even emerge but in opposite directions by driving the resonator from different directions. This ability to flexibly manipulate the system allows us to achieve directional entangled multiquanta emitters, and has also potential applications for building hybrid quantum networks and on-chip quantum communications.
Quantum squeezing, a cornerstone of quantum optics and photonics, has played a key role in achieving ultra-precision sensing and realizing nonreciprocal engineering. However, the nonreciprocal multiquanta emission has remained largely unexplored by using directional quantum squeezing. Here, the one-way photon-photon bundle emission in a compound system consisted of two coupled optical resonators and a two-level atom is investigated. It is found that the directional quantum squeezing induces the asymmetric frequency detuning and photon hopping interaction between the two resonators, leading to the directional excitation of the two-photon super-Rabi oscillation. In particular, by harnessing intrinsic dissipation of the system, two types of two-photon bundle emission can be selectively induced for the probe field input from one direction while it is prohibited with the probe from the other direction. This finding bridges the broad fields ranging from nonreciprocal physics to quantum squeezing optics and multiquanta emission control through an all-optical approach, which can enable potential applications in chiral quantum emitters and backscattering-immune photonic communications.
The controlled generation of nonclassical light beyond single photons remains a central challenge in quantum optics, due to the difficulty of enhancing multiphoton processes while suppressing lower-order excitations. Here we propose an interference-interaction-engineered scheme for programmable few-photon emission in a cavity-QED system of three atoms coupled to orthogonal cavity modes. By adiabatically eliminating an auxiliary Fabry-Pérot cavity, we generate a tunable cavity-mediated spin-exchange interaction
χ, which, combined with a controllable geometric phase
φ, reshapes the many-body dressed-state spectrum. This interplay enables selective addressing of excitation manifolds (
N=1,2,3), establishing a direct mapping between excitation structure and photon-emission channels. For
φ=0, constructive interference enhances the spectral anharmonicity of low-excitation manifolds, yielding tunable single- and two-photon emission associated with the
N=1 and
N=2 manifolds. In contrast, for
φ=2π/3, destructive interference suppresses lower-order excitation pathways and activates a resonant three-photon channel originating from the
N=3 manifold. Importantly, the cavity-mediated interaction
χ further enhances spectral separation between manifolds, enabling a substantial improvement in multiphoton purity while maintaining a sizable photon population. We demonstrate a three-order-of-magnitude enhancement in two-photon purity and more than two orders of magnitude improvement in three-photon emission. Our results establish a unified interference-interaction framework in which effective optical nonlinearities can be programmably engineered through phase and interaction, providing a scalable route toward high-purity multiphoton sources and programmable quantum photonic devices.
We present a study on manipulation and enhancement of multiphoton bundles emission under a moderate atom-cavity coupling, by constructing a two-photon Jaynes-Cummings model integrated with Kerr nonlinearity in a single atom-cavity system. We show that the vacuum-Rabi splittings for the n th dressed states can be significantly enhanced by Kerr interaction. This remarkable enhancement in energy-spectrum anharmonicity with the well-resolved multiphoton resonance facilitates the generation of special nonclassical states beyond the strong-coupling limit in the experiment. In particular, both two- and three-photon blockades are observed with adjusting the amplitude of the cavity-driving or atom-pump fields. Moreover, we discover that transitions between two- and three-photon bundles can be achieved through tuning the atom-cavity detuning or Kerr nonlinearity. It further showcases the three-photon blockade is substantially strengthened when both the cavity and atomic fields are jointly driven. Our proposal unveils a pathway for realizing highly controllable nonclassical states and quantum devices with combining two-photon Jaynes-Cummings interactions and Kerr nonlinearity, which may pave the way for versatile applications in quantum information science, e.g., all-optical switches and transistors. Published by the American Physical Society 2024
In this paper we propose a scheme for achieving simultaneous nonreciprocal photon blockade for two coupled spinning resonators, one of which contains an optical parametric amplifier (OPA). Rotating two resonators gives rise to opposite Sagnac-Fizeau shifts for input from different ends. Depending on the opposite shifts, quantum destructive interference emerges and disappears in two-photon excitation. The emergence of destructive interference results in photon blockade in two resonators simultaneously for one end input, while the lack of complete destructive interference makes the blockade disappear for the other end input. The simultaneous nonreciprocal blockade is tunable by controlling the amplitude of the probe field and the driving field applied on the OPA. Our work paves the way to develop simultaneous nonreciprocal single-photon devices in multiple modes, which have potential applications in multichannel topological and chiral quantum technologies.
A scheme of nonreciprocal conventional phonon blockade (PB) is proposed in a spinning optomechanical resonator coupled with a two-level atom. The coherent coupling between the atom and breathing mode is mediated by the optical mode with a large detuning. Due to the Fizeau shift caused by the spinning resonator, the PB can be implemented in a nonreciprocal way. Specifically, when the spinning resonator is driven from one direction, the single-phonon (1PB) and two-phonon blockade (2PB) can be achieved by adjusting both the amplitude and frequency of the mechanical drive field, while phonon-induced tunneling (PIT) occurs when the spinning resonator is driven from the opposite direction. The PB effects are insensitive to cavity decay because of the adiabatic elimination of the optical mode, thus making the scheme more robust to the optical noise and still feasible even in a low-Q cavity. Our scheme provides a flexible method for engineering a unidirectional phonon source with external control, which is expected to be used as a chiral quantum device in quantum computing networks.