Optomechanical Arrays Research Articles

Thermo-optic effect induced tunable phase controlled propagation of solitons in a Jaynes-Cummings-Hubbard model

The manipulation of light propagation has garnered significant attention in discrete periodic photon structures. In this study, we investigate the impact of an adjustable phase on soliton behavior within a one-dimensional (1D) coupled cavity array. Each cavity is doped with two-level qubits, and the system can be effectively described by a Jaynes-Cummings-Hubbard model (JC-Hubbard model). By numerically exploring the photonic phase, we reveal that it introduces an additional degree of flexibility in controlling soliton propagation. This flexibility encompasses dispersion relations, propagation direction, transverse velocity, and stability conditions. We observe that soliton styles transition with changes in the tunneling phase. At a phase of 0, solitons form due to the delicate balance between spatial dispersion and system nonlinearity. When the phase increases to π/2, solitons vanish because spatial dispersion is significantly suppressed. The underlying theory explains this suppression, which arises from the opposite phase ±θ. Interestingly, standard temporal solitons emerge in the discrete periodic cavity array. Our investigation has broader applicability extending to various discrete structures, encompassing but not limited to waveguide arrays and optomechanical cavity arrays.

Opto-mechanical stacked metamaterials for optical readout millimeter wave detection

An opto-mechanical stacked metamaterials is proposed. Different from traditional metamaterials, it adopts a separable design to realize the stacked structure of the lower and upper chips. It can break the metamaterial thickness limit and integrate absorbing/execution units on functional layer with a thickness less than one thousandth of a wavelength, enabling high-performance detection. We design and prepare a millimeter wave opto-mechanical stacked metamaterial array detector, whose upper chip is only 1/2133 of the wavelength, but the absorptivity is about 99 %. Unlike the traditional detectors that convert millimeter wave radiation into electrical signals, it converts the radiation into micromechanical deflections opto-mechanical structures, and then reads them out optically. It’s equivalent to converting the millimeter wave detection into visible light detection. An optical readout system was constructed to verify the detection performance. Experimental results show that the response time can reach 20 ms and the NEP (Noise Equivalent Power) is 1.1 × 10−10 W/Hz1/2.

Optimal design of optomechanical uncooled infrared focal plane array with integrated metalens

Optomechanical uncooled infrared (IR) detectors based on the thermal deformation of bi-material micro-cantilever have proved of significant potential in the IR imaging fields. However, compared to other uncooled infrared detectors, the optomechanical type relies on the mechanical deformation of the thermomechanical cantilevers, which compete for space with the absorbers and isolation beams, resulting in limited sensitivity. By integrating a designed metalens, large deformation, high thermal isolation, and high effective fill factor can be achieved simultaneously. Several pixel designs of optomechanical uncooled IR focal plane array (FPA) with designed integrated metalens are evaluated and optimized through numerical simulation. High thermal conversion efficiency and thermomechanical sensitivity μm K−1 are simultaneously achieved with an inherent noise-equivalent temperature difference(NETD) value of mK at the preset × pixels. Using Figure of Merit(FOM) as a comprehensive evaluation of NETD and response time, the optimized structure can be improved by up to 40% over the original structure.

Entanglement-enhanced optomechanical sensor array with application to dark matter searches

Squeezed light has long been used to enhance the precision of a single optomechanical sensor. An emerging set of proposals seeks to use arrays of optomechanical sensors to detect weak distributed forces, for applications ranging from gravity-based subterranean imaging to dark matter searches; however, a detailed investigation into the quantum-enhancement of this approach remains outstanding. Here, we propose an array of entanglement-enhanced optomechanical sensors to improve the broadband sensitivity of distributed force sensing. By coherently operating the optomechanical sensor array and distributing squeezing to entangle the optical fields, the array of sensors has a scaling advantage over independent sensors (i.e., sqrt{M}to M, where M is the number of sensors) due to coherence as well as joint noise suppression due to multi-partite entanglement. As an illustration, we consider entanglement-enhancement of an optomechanical accelerometer array to search for dark matter, and elucidate the challenge of realizing a quantum advantage in this context.

Nonlinear localized wave modes in optomechanical array

Abstract Optomechanical arrays have been used in many areas of research, from nonlinear optics to acoustics. In particular, the optomechanical array has been studied for its interesting properties such as strong optical force and high frequency resonance. In this work, we carry out the modulated wave patterns and nonlinear modes by driving one end of the optomechanical array in the forbidden gap. We use the discrete nonlinear Schrödinger equation with self-Kerr nonlinear term to determine the threshold amplitude. We then consider the driven amplitude to drive the model above the phonon band. The result is a train of waves with an asymmetric shape in the forbidden gap. For large values of the nonlinear term, we observe unstable modes of the modulation growth rates and the modulated wave patterns also emerge from the driven optomechanical array. At the specific cell index, the pulse train increases in amplitude and brings instability in the bandgap. These results open a new feature of the position modulated self-Kerr nonlinear term as an internal force to drive the nonlinear Schrödinger equation.

Synchronization of silicon thermal free-carrier oscillators

Recent exploration of collective phenomena in oscillator arrays has highlighted the potential to access a range of physical phenomena, from fundamental quantum many-body dynamics to the solution of practical optimization problems using photonic Ising machines. Spontaneous oscillations often arise in these oscillator arrays as an imbalance between gain and loss. Due to coupling between individual arrays, the spontaneous oscillation is constrained and leads to interesting collective behavior, such as synchronized oscillations in optomechanical oscillator arrays, ferromagnetic-like coupling in delay-coupled optical parametric oscillators, and binary phase states in coupled laser arrays. A key aspect of arrays is not only the coupling between the individuals but also their compliance toward neighbor stimuli. One self-sustaining photonic oscillator that can be readily implemented in a scalable foundry-based technology is based on the interaction of free carriers, temperature, and the optical field of a resonant silicon photonic microcavity. Here, we demonstrate that these silicon thermal free-carrier (FC) oscillators are extremely compliant to external excitation and can be synchronized up to their 16th harmonic using a weak seed. Exploring this unprecedented compliance to external stimuli, we also demonstrate robust synchronization between two thermal FC oscillators.

Synthetic magnetism for solitons in optomechanical array

Discrete optical and mechanical solitonic waves are widely used for photonic/phononic information processing. Here we propose a synthetic magnetism to generate and to control solitonic waves in 1D−optomechanical array. Each optomechanical cavity in the array couples to its neighbors through photon and phonon coupling. We create the synthetic magnetism by modulating the phonon hopping rate through both the modulation of frequency and phase between resonators at different sites. When the synthetic magnetism effect is not taken into account, the mechanical coupling play a crucial role of controlling and switching the waves from bright to dark solitons, and it even induces rogue wave-like a shape in the array. For enough mechanical coupling strength, the system enters into a strong coupling regime through splitting/crossing of solitonic waves, leading to multiple waves propagation in the array. Under the synthetic magnetism effect, the phase of the modulation enables a good control of the wave propagation, and it also switches soliton shape from bright to dark, and even induces rogue waves as well. Similarly to the mechanical coupling, the synthetic magnetism offers another flexible way to generate plethora of solitonic waves for specific purposes. This work opens new avenues for optomechanical platforms and sheets light on their potentiality of controlling and switching solitonic waves based on synthetic magnetism.

Homodyne coherent quantum noise cancellation in a hybrid optomechanical force sensor

In this paper we propose an experimentally viable scheme to enhance the sensitivity of force detection in a hybrid optomechanical setup assisted by squeezed vacuum injection, beyond the standard quantum limit (SQL). The scheme is based on a combination of the coherent quantum noise cancellation (CQNC) strategy with a variational homodyne detection of the cavity output spectrum in which the phase of the local oscillator is optimized. In CQNC, realizing a negative-mass oscillator in the system leads to exact cancellation of the backaction noise from the mechanics due to destructive quantum interference. Squeezed vacuum injection enhances this cancellation and allows sub-SQL sensitivity to be reached in a wide frequency band and at much lower input laser powers. We show here that the adoption of variational homodyne readout enables us to enhance this noise cancellation up to $40\phantom{\rule{3.33333pt}{0ex}}\mathrm{dB}$ compared to the standard case of detection of the optical output phase quadrature, leading to a remarkable force sensitivity of the order of ${10}^{\ensuremath{-}19}\phantom{\rule{0.28em}{0ex}}\mathrm{N}/\sqrt{\mathrm{Hz}}$, about $70%$ enhancement compared to the standard case. Moreover, we show that at nonzero cavity detuning, the signal response can be amplified at a level three to five times larger than that in the standard case without variational homodyne readout, improving the signal-to-noise ratio. Finally, the variational readout CQNC developed in this paper may be applied to other optomechanical-like platforms such as levitated systems and multimode optomechanical arrays or crystals as well as Josephson-based optomechanical systems.

Coherent mechanical noise cancellation and cooperativity competition in optomechanical arrays

Studying the interplay between multiple coupled mechanical resonators is a promising new direction in the field of optomechanics. Understanding the dynamics of the interaction can lead to rich new effects, such as enhanced coupling and multi-body physics. In particular, multi-resonator optomechanical systems allow for distinct dynamical effects due to the optical cavity coherently coupling mechanical resonators. Here, we study the mechanical response of two SiN membranes and a single optical mode, and find that the cavity induces a time delay between the local and cavity-transduced thermal noises experienced by the resonators. This results in an optomechanical phase lag that causes destructive interference, cancelling the mechanical thermal noise by up to 20 dB in a controllable fashion and matching our theoretical expectation. Based on the effective coupling between membranes, we further propose, derive, and measure a collective effect, cooperativity competition on mechanical dissipation, whereby the linewidth of one resonator depends on the coupling efficiency (cooperativity) of the other resonator.

Generalized Su-Schrieffer-Heeger Model in One Dimensional Optomechanical Arrays

We propose an implementation of a generalized Su-Schrieffer-Heeger (SSH) model based on optomechanical arrays. The topological properties of the generalized SSH model depend on the effective optomechanical interactions which can be controlled by strong driving fields. Three phases including one trivial and two distinct topological phases are found in the generalized SSH model. The phase transition can be observed by turning the strengths and phases of the effective optomechanical interactions via adjusting the driving fields. Moreover, four types of edge states can be created in generalized SSH model of an open chain under single-particle excitation, and the dynamical behaviors of the excitation in the open chain are related to the topological properties under the periodic boundary condition. We show that the edge states can be pumped adiabatically along the optomechanical arrays by periodically modulating the amplitude and frequency of the driving fields, and the state pumping is robust against small disorders. The generalized SSH model based on the optomechanical arrays provides us a controllable platform to engineer topological phases for photons and phonons, which may have potential applications in controlling the transport of photons and phonons.

Topologically protected optomechanically induced transparency in a one-dimensional optomechanical array

We investigate the optomechanically induced transparency (OMIT) in an optomechanical lattice. By controlling the frequency of the external drivings in a periodic manner, the optomechanical lattice can be regarded as a Su-Schrieffer-Heeger model. By calculating the local photon density of states for the system, we investigate the response of the system to a weak probe field. In the nondeep topological nontrivial phase, we find that the system has two nondegenerate edge modes due to the finite size of the system. In this regime, a narrow transparency window of the probe field, which is much narrower than the scale set by photon decay, can be observed due to the destructive interference of the probe field absorption paths induced by the two nondegenerate edge modes. In the deep topological nontrivial phase, the two edge modes become degenerate and the narrow transparency window changes into a wide absorption window. The OMIT of the optomechanical array can also be observed in the presence of large disorders of the many-photon optomechanical couplings. Our work generalizes the OMIT of a single optomechanical cavity to a topological optomechanical system and might have potential applications in quantum information processing and quantum optical devices.

Discrete solitons in nonlinear optomechanical array

The detection of the solitons whose the propagation is spatially localized on the array is an interesting feature for experimental purposes. Here, we investigate the effect of position-modulated self-Kerr nonlinearity on discrete soliton propagating in an optomechanical array. The optomechanical cells are coupled to their neighbors by optical channels, and each cell supports the self-Kerr nonlinear term. Modulational Instability (MI) together with numerical simulations are carried out to characterize the behavior of the solitonic waves. It results that the nonlinear term shortens the transient regime of the temporal solitonic waves, which allows the wave propagation to be confined along specific cells. As the nonlinear term increases, the pulsed shape of soliton waves get sharped and highly peaked. For a strong enough value of the nonlinear term, the waves feature chaos-like motion. Owing to these results, the position-modulated self-Kerr nonlinear term manifests itself as being an energy source for the solitonic waves, allowing to the generated solitons to propagate during a long time while acquiring energy. These results shed light on the fact that nonlinear optomechanical platforms could be used to generate long-lived temporal localized solitons and even chaotic solitonic waves, which are good prerequisites for information processing purposes.

Dynamical bipartite and tripartite entanglement of mechanical oscillators in an optomechanical array

We theoretically propose a method to generate tripartite entanglement of three mechanical oscillators in an optomechanical array. We consider a system comprised of three bichromatically driven optomechanical systems which are coupled to each other via Coulomb interaction of the mechanical oscillators. We show that, for small Coulomb coupling strength, steady tripartite entanglement of the three mechanical oscillators with time periodicity can be generated due to the combined effect of the two-tone drivings and the Coulomb coupling. At large Coulomb coupling strength, the tripartite entanglement exhibits steady entanglement sudden death and revival. The duration of entanglement death during one period can be controlled by the Coulomb coupling strength. The tripartite entanglement is robust against the mechanical thermal noise. Our paper provides us a route for exploring and exploiting controllable and robust multipartite entanglement among macroscopic mechanical oscillators.

Optical spatial filtering readout techniques for IR/THz imaging and their performance analysis

Optical spatial filtering readout techniques (OSFRTs), such as knife-edge filtering and circular hole filtering, are broadly used in optomechanical microcantilever focal plane arrays for infrared (IR)/terahertz (THz) imaging. In order to further improve the responsivity of IR/THz imaging, it is important to improve the optical readout responsivity (ORR). However, the shape and location of the optical spatial filter cannot be well optimized for lack of a unified theoretical ORR model of OSFRTs. This paper gives and experimentally validates a unified ORR model of OSFRTs. Based on this model, the influence of the shape and location of the four commonly used spatial filters on the imaging resolution and light utilization efficiency is discussed. Both theory and experiment show that the slit filter has higher optical readout responsivity than the knife-edge filter and better light utilization efficiency than the rectangular or circular hole filters. Therefore, the slit filter should be the best of the four commonly used filters.

Enhanced optomechanically induced transparency via atomic ensemble in optomechanical system.

We investigate the optomechanically induced transparency phenomena assisted through cavity optomechanical system. The system consists of an optical cavity system filled with the two-level atomic ensemble and driven by a weak probe laser as well as a strong coupling fields. Under different driving conditions, the system can exhibit the phenomena of optomechanical induced transparency dip. Specifically, the width of the transparency window increases with an increase in the coupling constant, while decreasing with an increase in atomic decay rate. Furthermore, the induced transparency phenomena are strongly affected by the number of atoms, coupling, and the decay rate. It is found that the larger the number of atoms, the wider the window of induced transparency, and therefore enhance the depth of transparency window. These results may have spectacular applications for slowing and on-chip storage of light pulses by the use of a micro-fabricated optomechanical array.

Dynamics of Entanglement in Optomechanical Cavity Arrays: Localization-Delocalization Transition

Dynamics of entanglement in an optomechanical cavity array, as an open quantum system is investigated. Time evolution of entanglement transfer between system parts is studied by direct numerical solution of the Lindblad equation. Entanglement swapping between array components as well as the localization of entanglement in an intended part of the system are numerically analyzed.

Discrete optics in optomechanical waveguide arrays.

The propagation properties of light in optomechanical waveguide arrays (OMWAs) are studied. Due to the strong mechanical Kerr effect, the optical self-focusing and self-defocusing phenomena can be realized in the arrays of subwavelength dielectric optomechanical waveguides with the milliwatt-level incident powers and micrometer-level lengths. Compared with the conventional nonlinear waveguide arrays, the required incident powers and lengths of the waveguides are decreased by five orders of magnitude and one order of magnitude, respectively. Furthermore, by adjusting the deformation of the nanowaveguides through a control light, the propagation path of the signal light in the OMWA can be engineered, which could be used as a splitting-ratio-tunable beam splitter. This Letter provides a new platform for discrete optics and broadens the application of integrated optomechanics.

Spatial localization and pattern formation in discrete optomechanical cavities and arrays

We investigate theoretically the generation of nonlinear dissipative structures in optomechanical (OM) systems containing discrete arrays of mechanical resonators. We consider both hybrid models in which the optical system is a continuous multimode field, as it would happen in an OM cavity containing an array of micro-mirrors, and also fully discrete models in which each mechanical resonator interacts with a single optical mode, making contact with Ludwig and Marquardt (2013 Phys. Rev. Lett. 101, 073603). Also, we study the connections between both types of models and continuous OM models. While all three types of models merge naturally in the limit of a large number of densely distributed mechanical resonators, we show that the spatial localization and the pattern formation found in continuous OM models can still be observed for a small number of mechanical elements, even in the presence of finite-size effects, which we discuss. This opens new venues for experimental approaches to the subject.

Superfluid–Mott insulator quantum phase transition in hybrid cavity optomechanical arrays

A two-dimensional hybrid cavity optomechanical array formed by an optomechanical cavity embedded with a two-level atom in each site is introduced to discuss the superfluid–Mott insulator quantum phase transition of light. On account of the optomechanical coupling effects stemmed from the coupled movable oscillator, the energy spectrum of the system changes, and an effective on-site repulsive interaction is reformed by modulating the optomechanically controlled parameters. By adjusting the detuning, an intersection between different critical chemical potentials can be found together with a disappearance of certain Mott lobes physically. The pronounced optomechanical coupling strength is in favor of the Mott insulator phase due to the enhanced effective on-site interactions. Additionally, the Kerr-nonlinearity reduces the average excitation of the high Mott insulator state and diminishes the superfluid regime. The results obtained here provide a novel image for characterizing the quantum phase transitions in optomechanical array systems, which will offer valuable insight for quantum simulations.

Generation of the bipartite entanglement and correlations in an optomechanical array

In this paper, we study the remote bipartite entanglement and correlations between the neighboring cavity and movable mirror using an optomechanical array, in which the optical cavities are coupled to one oscillating end-mirror through a photon hopping process. Under the linearization approximation, the stationary bipartite continuous-variable entanglement and quantum correlations are quantified through logarithmic negativity and correlation functions of two non-Hermitian operators, respectively. Remarkably, our numerical simulation exhibits a generation of bipartite correlation behavior between cavity–oscillating mirror and cavity–cavity subsystems through the applicable choice of optical cavity detunings and photon hopping coupling strength. The system also offers the possibility of remote bipartite entanglement with the neighboring cavity and movable mirror. We further show that the amount of quantum correlation between subsystems can be achieved for small photon hopping coupling strengths and small effective temperatures. It is found that the generation of bipartite quantum correlations between the cavity mode and oscillating mirror can be transferred entirely through photon hopping coupling strength. Our results may have potential applications for the realization of optomechanical crystals platform and continuous-variable quantum information interfaces.