We demonstrate a new type of transition within the strong coupling regime, which alters the coupling mechanism in multimode cavities. We show that this transition drastically modifies the Hamiltonian describing the polaritons, such that different cavity modes are either entangled via the material or completely decoupled. This decoupling transition occurs due to the competition between the dissipation in the material and the finite group velocity, which governs the propagation of information across the cavity and among the molecules. The results indicate that the velocity of light, which is often not taken into account in cavity quantum electrodynamics, plays a crucial role in the formation of cavity polaritons and their dynamics.
We analyzed multimode Josephson junctions with exciton-polaritons (polaritonic Josephson junctions) when several coupling mechanisms of fundamental and excited states are present. The applied method is based on Keldysh-Green function formalism and takes into account polariton pseudospin. We found that mean value of circular polarization degree in intrinsic Josephson oscillations and microscopic quantum self-trapping follow an oscillator behavior whose renormalizes due to intermode interactions. The effect of an additional transfer of particles over junction barrier occurring in multimode appro…
Microcavity polaritons are bosonic light-matter particles that can emit coherent radiation without electronic population inversion via bosonic scattering. This phenomenon, known as polariton lasing, strongly depends on the polaritons' confinement. Shrinking the polaritons' mode volume increases the interactions mediated by their excitonic part, and thereby the density-dependent blueshift of the polariton to a higher energy is enhanced. Previously, polariton lasing has been demonstrated in micropillars with diameters larger than three microns, in grating based cavities, fiber cavities and photo…
Enhancement of far-field thermal emission via polaritonic cavity modes
The University of Tokyo（东京大学）；CNRS-IIS IRL 2820（法国国家科学研究中心-东京工业科学研究所联合研究室）；Sorbonne Université（索邦大学）；Institut des Nanosciences de Paris (INSP)（巴黎纳米科学研究所）；Univ Gustave Eiffel（格夫·埃菲尔大学）；ESYCOM lab, UMR 9007 CNRS（法国国家科学研究中心UMR 9007 ESYCOM实验室）；Université PSL（巴黎文理研究大学）；Institut Langevin, ESPCI Paris（巴黎高等物理化工学院朗之万研究所）
Efficient coupling between on-chip sources and cavities plays a key role in silicon photonics. However, despite the importance of this basic functionality, there are few systematic design tools to simultaneously control coupling between multiple modes in a compact resonator and a single waveguide. Here, we propose a large-scale adjoint optimization approach to produce wavelength-scale waveguide--cavity couplers operating over tunable and broad frequency bands. We numerically demonstrate couplers discovered by this method that can achieve critical, or nearly critical, coupling between multi-rin…
Chiral Nonlinear Polaritonics with van der Waals Metasurfaces
Ludwig-Maximilians-Universität München（慕尼黑大学）；Universidade Federal de Pernambuco（伯南布哥联邦大学）；Monash University（莫纳什大学）；Imperial College London（帝国理工学院）；Shubnikov Institute of Crystallography, National Research Centre "Kurchatov Institute"（库尔恰托夫国家研究中心舒比尼科夫晶体学研究所）；National University of Science and Technology ‘MISIS’（国立科技大学 MISIS）；Australian National University（澳大利亚国立大学）
We present a beyond-mean-field approach to predict the nature of organic polariton lasing, accounting for all relevant photon modes in a planar microcavity. Starting from a microscopic picture, we show how lasing can switch between polaritonic states resonant with the maximal gain, and those at the bottom of the polariton dispersion. We show how the population of non-lasing modes can be found, and by using two-time correlations, we show how the photoluminescence spectrum (of both lasing and non-lasing modes) evolves with pumping and coupling strength, confirming recent experimental work on the…
We develop a theory for the dynamics of the density matrix describing a multimode polariton condensate. In such a condensate several single-particle orbitals become highly occupied, due to stimulated scattering from reservoirs of high-energy excitons. A generic few-parameter model for the system leads to a Lindblad equation which includes saturable pumping, decay, and condensate interactions. We show how this theory can be used to obtain the population distributions, and the time-dependent first- and second-order coherence functions, in such a multimode condensate. As a specific application, w…
Chirality routing non-polaritonic vacuum correlations in Landau polaritons
College of Physical Sciences and Engineering, University Mohammed VI Polytechnic（物理科学与工程学院，穆罕默德六世polytechnic大学）；Jülich Supercomputing Centre, Institute for Advanced Simulation, Forschungszentrum Jülich（于利希超级计算中心，高级模拟研究所，于利希研究中心）；Institut für Theoretische Physik, Universität Tübingen（理论物理研究所，蒂宾根大学）；Department of Chemistry, Princeton University（化学系，普林斯顿大学）
We study the interplay between disorder and light-matter coupling by considering a disordered one-dimensional chain of lossy dipoles coupled to a multimode optical cavity, through a microscopically derived Hamiltonian. Such a system, hosting polaritonic excitations, may be realized experimentally in a wide range of platforms under strong light-matter coupling. By analyzing both the eigenspectrum and the driven-dissipative transport properties of our system, we find that in the strong-coupling regime, increasing disorder leads almost uncoupled dark states to acquire a photonic part, allowing th…
The way molecules absorb, transfer, and emit light can be dramatically modified by coupling them to optical cavities. The extent of the modification is often defined by the cavity-molecule coupling strength. Evaluating this coupling strength for different types of modes supported by a cavity is crucial in designing cavities for molecule-cavity coupling. Here we probe a unique multimode cavity, a dielectric microsphere, also called a soft-cavity, which supports two distinct types of mode, dark-field scattering (DFS) modes and whispering gallery modes (WGM). Though seemingly similar, these modes…
We study a driven-dissipative array of coupled nonlinear optical resonators by numerically solving the Von Neumann equation for the density matrix. We demonstrate that quantum correlated states of many photons can be generated also in the limit where the nonlinearity is much smaller than the losses, contrarily to common expectations. Quantum correlations in this case arise from interference between different pathways that the system can follow in the Hilbert space to reach its steady state under the effect of coherent driving fields. We characterize in particular two systems: a linear chain of…
We present a scheme to generate an artificial gauge field for the system of neutral bosons, represented by polaritons in micropillars arranged into a square lattice. The splitting between the two polarizations of the micropillars breaks the time-reversal symmetry (TRS) and results in the effective phase-dependent hopping between cavities. This can allow for engineering a nonzero flux on the plaquette, corresponding to an artificial magnetic field. Changing the phase, we observe a characteristic Hofstadter's butterfly pattern and the appearance of chiral edge states for a finite-size structure.…
Exciton polaritons in semiconductor microcavities exhibit many fundamental physical effects, with some of them amenable to being controlled by external fields. The polariton transport is affected by the polaritonic spin-orbit interaction, which is caused by the splitting of transverse-electric and transverse-magnetic (TE-TM) modes. This is the basis for a polaritonic Hall effect, called optical spin Hall effect (OSHE), which is related to the formation of spin/polarization textures in momentum space, determining anisotropic ballistic transport, as well as related textures in real space. Owing …
We introduce a new multimode cavity QED architecture for superconducting circuits which can be used to implement photonic memories, more efficient Purcell filters, and quantum simulations of photonic materials. We show that qubit interactions mediated by multimode cavities can have exponentially improved contrast for two qubit gates without sacrificing gate speed. Using two-qubits coupled via a three-mode cavity system we spectroscopically observe multimode strong couplings up to 102MHz and demonstrate suppressed interactions off-resonance of 10kHz when the qubits are ~600MHz detuned from the …
Can we couple multiple molecular species to soft-cavities? The answer to this question has relevance in designing open cavities for polaritonic chemistry applications. Due to the differences in adhesiveness it is difficult to couple multiple molecular species to open cavities in a controlled and precise manner. In this letter, we discuss the procedure to coat multiple dyes, TDBC and S2275, using a layer-by-layer deposition technique onto a dielectric microsphere so as to facilitate the multi molecule coupling. We observed the formation of a middle polariton branch due to the inter-molecular mi…
A series of experiments demonstrate that strong light-matter coupling between vibrational excitations in isotropic solutions of molecules and resonant infrared optical microcavity modes leads to modified thermally-activated kinetics. However, Feist and coworkers [\emph{Phys. Rev. X.}, \textbf{9}, 021057(2019)] have recently demonstrated that, within transition state theory, the effects of strong light-matter coupling with reactive modes are electrostatic and essentially independent of light-matter resonance or even of the formation of vibrational polaritons. To analyze this puzzling theoretica…
We investigate an acoustical analog of circuit quantum electrodynamics that facilitates compact high-Q (${>}20,000$) microwave-frequency cavities with dense spectra. We fabricate and characterize a device that comprises a flux tunable transmon coupled to a $300\,\mathrm{μm}$ long surface acoustic wave resonator. For some modes, the qubit-cavity coupling reaches $6.5\,\mathrm{MHz}$, exceeding the cavity loss rate ($200\,\mathrm{kHz}$), qubit linewidth ($1.1\,\mathrm{MHz}$), and the cavity free spectral range ($4.8\,\mathrm{MHz}$), placing the device in both the strong coupling and strong multim…
Manipulation of chemical reactivity often involves changing reagents or environmental conditions. Alternatively, strong coupling between light and matter offers a way to tunably hybridize their physicochemical properties and thereby change reaction dynamics without synthetic modifications to the starting material. Here, we theoretically design a polaritonic (hybrid photonic-molecular) device that supports ultrafast tuning of reaction yields even when the catalyst and its reactant are spatially separated across several optical wavelengths. We demonstrate how photoexcitation of a `remote catalys…
We demonstrate Resonant Tunneling Diodes, embedded in double metal cavities, strongly coupled to the cavity field, while maintaining their electronic properties. We measure the polariton dispersion and find a relative vacuum Rabi splitting of 16%, which explicitly qualifies for the strong-coupling regime. Additionally we show that electronic transport has a significant influence on the polaritons by modulating the coupling strength. The merge between electronic transport and polaritonic physics in our devices opens up a new aspect of cavity quantum electro-dynamics and integrated photonics.
We develop a theory of cavity quantum electrodynamics for a 2D electron gas in the presence of Rashba spin-orbit coupling and perpendicular static magnetic field, coupled to spatially nonuniform multimode quantum cavity photon fields. We demonstrate that the lowest polaritonic frequency of the full Hamiltonian can vanish for realistic parameters, achieving the Dicke superradiant quantum phase transition. This singular behaviour originates from soft spin-flip transitions possessing a non-vanishing dipole moment at non-zero wave vectors and can be viewed as a magnetostatic instability.
When the interaction between a molecular system and confined light modes in an optical or plasmonic cavity is strong enough to overcome the dissipative process, hybrid light-matter states (polaritons) become the fundamental excitations in the system. The mixing between the light and matter characters modifies the photophysical and photochemical properties. Especially, it was reported that these polaritons can be employed to control photochemical reactions, charge and energy transfer, and other processes. In addition, according to recent studies, vibrational strong coupling can be employed to r…
We review the field of cavity optomechanics, which explores the interaction between electromagnetic radiation and nano- or micromechanical motion. This review covers the basics of optical cavities and mechanical resonators, their mutual optomechanical interaction mediated by the radiation pressure force, the large variety of experimental systems which exhibit this interaction, optical measurements of mechanical motion, dynamical backaction amplification and cooling, nonlinear dynamics, multimode optomechanics, and proposals for future cavity quantum optomechanics experiments. In addition, we d…
