arXiv subjects

Anael Ben-Asher

Publications and source records attributed to Anael Ben-Asher.

4 recordsLinked to original sources

arXiv2025

Interference-induced cavity resonances and imaginary Rabi splitting

Polaritons are usually described within single-mode cavity QED models. However, nanophotonic environments typically involve several modes that spectrally overlap and interfere, giving rise to sharp dip features such as Fano profiles in the electromagnetic spectral density. Here, we identify these features as interference-induced resonances, effective electromagnetic modes with complex, non-Hermitian couplings to quantum emitters. We show that these modes hybridize with emitters to form polaritons even when the system parameters do not satisfy the single-mode strong-coupling criterion. Moreover, the resulting polaritons differ in their decay rates, a phenomenon we term imaginary Rabi splitting. Extending the analysis to ensembles, we find that coupling to interference-induced resonances produces long-lived polaritons that can outlast excitonic dark states. Numerical simulations of a realistic hybrid metallodielectric platform confirm these predictions and demonstrate their robustness against disorder and loss. Our results reveal a new polaritonic regime beyond the single-mode description, offering new opportunities for controlling light-matter interactions in complex electromagnetic environments.

physics.optics↗

arXiv2024

Enhanced photoisomerization with hybrid metallodielectric cavities based on mode interference

The ability to control chemical reactions by coupling organic molecules to confined light in a cavity has recently attracted much attention. While most previous studies have focused on single-mode photonic or plasmonic cavities, here we investigate the effect of hybrid metallodielectric cavities on photoisomerization reactions. Hybrid cavities, which support both photonic and plasmonic modes, offer unique opportunities that arise from the interplay between these two distinct types of modes. Specifically, we demonstrate that interference in the spectral density due to a narrow photonic mode and a broad plasmonic mode that are coupled to each other enables hybrid cavities to provide an energy-selective Purcell effect. This effect enhances electronic relaxation only to the desired molecular geometry, providing the ability to increase the yield of photoisomerization reactions. As a test case, we study the asymmetric proton transfer reaction in the electronic excited state of 3-aminoacrolein. Our results, which are robust for a range of realistic cavity parameters, highlight the advantages of hybrid cavities in cavity-induced photochemical processes.

physics.chem-ph↗

arXiv2024

Memory loss is contagious in open quantum systems

Memoryless (Markovian) system-bath interactions are of fundamental interest in physics. While typically, the absence of memory originates from the characteristics of the bath, here we demonstrate that it can result from the system becoming lossy due to the Markovian interaction with a second bath. This uncovers an interesting interplay between independent baths and suggests that Markovianity is ``contagious'', i.e., it can be transferred from one bath to another through the system with which they both interact. We introduce a Bloch-Redfield-inspired approach that accounts for this distinct origin of Markovianity and uniquely combines non-Hermitian Hamiltonian formalism with master equations. This method significantly improves the description of the interaction between a lossy system (associated with a Lindblad master equation) and a non-Markovian bath, reducing the computational demands of complex system-bath setups across various fields.

quant-ph↗

arXiv2024

Non-Hermitian Anharmonicity Induces Single-Photon Emission

Single-photon sources are in high demand for quantum information applications. A paradigmatic way to achieve single-photon emission is through anharmonicity in the energy levels, such that the absorption of a single photon from a coherent drive shifts the system out of resonance and prevents absorption of a second one. We identify a novel mechanism for single-photon emission through non-Hermitian anharmonicity, i.e., anharmonicity in the losses instead of in the energy levels. We demonstrate the mechanism in two types of systems, including a feasible setup consisting of a hybrid metallodielectric cavity weakly coupled to a two-level emitter, and show that it induces high-purity single-photon emission at high repetition rates.

quant-ph↗