Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2606.31212

Unresolved-Sideband Optomechanics with Hexagonal Boron Nitride: Induced Transparency, Gain, and Frequency Combs

Francesco Fogliano, Thibaud Ruelle, David Jaeger, Martino Poggio

physics.opticscond-mat.mes-hallquant-phSubmitted Jun 30, 2026• Announced Jul 1, 2026
arXivHTMLPDF

Abstract

Optomechanically induced transparency (OMIT) is usually modeled and studied in the resolved-sideband regime, but many compact microcavity platforms operate in the unresolved-sideband limit $(κ\gg Ω_m)$. Here we investigate OMIT in this regime using a tunable fiber-based Fabry-Perot microcavity coupled to a suspended hexagonal boron nitride (hBN) drum resonator in a membrane-in-the-middle geometry. The system achieves a large single-photon coupling rate of $g_0/2π\sim 180$ kHz and exhibits strong radiation-pressure backaction. By measuring OMIT spectra as a function of pump power and cavity detuning, we observe a crossover from a transparency-like dip to a gain feature in the reflected response. These maps are quantitatively reproduced by the full linearized optomechanical response, demonstrating the breakdown of the standard rotating-wave approximation used in the resolved-sideband limit. Finally, we drive the system into a nonlinear regime to generate optomechanical frequency combs. These results establish hBN fiber-cavities as a versatile architecture for unresolved-sideband optomechanics, nonlinear dynamics, and hybrid device integration.

Comments
Main text: 10 pages, 5 figures; supplementary: 52 pages, 25 figures

Related papers

Optomechanical systems with a Fano membrane in the middle

Lei Du, Aymeric Frerejean, Witlef Wieczorek +2 more

Conventional membrane-in-the-middle (MIM) optomechanical systems offer limited control over the optical linewidth, which can limit their performance when operating in the unresolved-sideband regime. We investigate cavity optomechanics with a photonic-crystal Fano membrane placed at the center of a Fabry-Pérot (FP) cavity. In contrast to a conventional dielectric membrane, the photonic-crystal membrane supports a localized optical resonance, which hybridizes with the cavity field and enables spectral engineering of the relevant optical modes. Besides the usual dispersive optomechanical coupling associated with cavity-length changes, the membrane motion also modifies the Fano-mode resonance and its hybridization with the cavity field. We consider two limits set by the membrane reflectivity: a transparent-membrane regime with a single FP-like mode, and a reflective-membrane regime with two coupled subcavity modes. In the latter case, only the symmetric cavity mode hybridizes with the Fano mode, while the antisymmetric mode remains decoupled. Using quantum Langevin equations together with a transfer-matrix description of the optical scattering problem, we show that the Fano-induced hybridization can generate narrow optical normal modes that remain efficiently accessible to the external drive for experimentally realistic parameters. These modes can provide effective sideband resolution and enable ground-state cooling of the membrane motion even when the bare cavity is in the unresolved-sideband regime. Our results establish Fano MIM systems as a promising platform for spectral and optomechanical engineering.

physics.opticsCross-listedarXiv:2607.22526•Jul 27, 2026

Optomechanically induced transparency with Bose–Einstein condensate in double-cavity optomechanical system

Liwei Liu, Duojie Gengzang, Xiu-Jia An +1 more

We propose a novel technique of generating multiple optomechanically induced transparency (OMIT) of a weak probe field in hybrid optomechanical system. This system consists of a cigar-shaped Bose–Einstein condensate (BEC), trapped inside each high finesse Fabry-Pérot cavity. In the resolved sideband regime, the analytic solutions of the absorption and the dispersion spectrum are given. The tunneling strength of the two resonators and the coupling parameters of the each BEC in combination with the cavity field have the appearance of three distinct OMIT windows in the absorption spectrum. Furthermore, whether there is BEC in each cavity is a key factor in the number of OMIT windows determination. The technique presented may have potential applications in quantum engineering and quantum information networks.

Chinese Physics B•Mar 1, 2018•9 citations

Mechanical quality factor estimation from a nonlinear optical cavity response

Zohran Ali, Davide Tomasella, Daniel Allepuz-Requena +2 more

Intrinsic damping rate and quality factor ($Q$) are key parameters in optomechanical systems. However, in high-Q devices, their measurement is often challenging because probe-induced dynamical backaction (DBA) and the need to resolve and accurately track the mechanical resonance limit the performance of state-of-the-art techniques. Here, we introduce an all-optical ringdown method in the unresolved-sideband regime that exploits the nonlinear, time-averaged optical response induced by strong mechanical motion. We derive an analytical model of the time-averaged optical cavity response probed by a weak frequency-scanning laser. During the evolution of the mechanical oscillator, the excited motion modulates the Lorentzian lineshape into a double-horned profile whose peak separation enables an accurate estimation of the modulation amplitude. Tracking this response during the mechanical ringdown allows the intrinsic damping rate to be determined without resolving the mechanical oscillation. We apply the method to a density-modulated phononic crystal membrane placed inside a high-finesse cavity and obtain mechanical quality factors consistent with independent measurements on the same platform. Our method requires a minimal optical setup, while offering an in situ diagnostic and reduced impact from probe-induced DBA and robustness against measurement noise. Finally, the model can describe other resonant systems dispersively coupled to coherent frequency modulations, providing new insights and measurement strategies that expand beyond the optomechanical platform.

physics.opticsCross-listedarXiv:2609.07393•Sep 8, 2026

Dissipative acousto-mechanical parametric interface between high-overtone acoustics and flexural phonons

Xun Ji, Huanying Sun, Longhao Wu +4 more

High-overtone bulk acoustic wave resonators (HBARs) promise advanced phononics, yet achieving nonlinearity remains challenging. We demonstrate a radiation-pressure-type parametric interaction between GHz HBARs and low-frequency flexural modes in a suspended silicon nitride membrane, where mechanical displacement modulates the external dissipation rate to enable dissipative acousto-mechanical coupling. Benefiting from the high quality factor, the system enters the resolved-sideband regime at room temperature, yielding acousto-mechanically induced transparency. We observe tunable Kerr nonlinearity and generate coherent HBAR frequency combs via two-tone driving. Notably, our dissipative coupling strength is 20 times larger than the dispersive coupling, the highest ratio among reported hybrid dissipative-dispersive coupling systems, resulting in the experimental observation of amplification in the reflection spectra under red-sideband driving. The ability to interface dense HBAR modes with a common mechanical resonator provides a scalable on-chip platform for multimode phononic information processing, with quantum phononics potentially achievable at sub-Kelvin temperatures.

quant-pharXiv:2605.24581•May 26, 2026

Perfect optomechanically induced transparency and slow light in an Rydberg atom-assisted optomechanical system

Xin Wang, Fei-Fan Ren, Song Hee Han +2 more

Rydberg atoms have attracted considerable attention due to their several singular properties, such as strong long-range interactions, extremely long lifetimes, and very large polarizability. These characteristics make Rydberg atoms a good candidates for cavity quantum electrodynamics, quantum information, and many-body physics. Recently, the study of optomechanics has become a rapidly developing field due to its important applications in cooling of mechanical resonators, implementing precision measurements, slowing light, and preparing quantum entanglement. Obviously, optomechanical systems pave the way for quantum information processing and quantum communication. Specially, there is significant interest in quantum optomechanics due to its high compatibility that can be combined, to build hybrid systems for certain purposes, with the ultracold atoms, a superconducting single electron transistor, a magnetostrictive actuation, a charged oscillator resonator, etc. In this work, we investigate the optomechanically induced transparency (OMIT) and the resulting effect of slow light in a hybrid system composed of a Rydberg atomic ensemble embedded inside a simple optomechanical cavity. As a typical effect of destructive quantum interference, OMIT is widely used in quantum optics and quantum information processing. Based on the Rydberg blockade effect, a Rydberg atomic ensemble in the same blockade region embedded inside an optomechanical cavity can be regarded as a superatom that contains only a single Rydberg excitation. Therefore, the problem of exponentially increasing system size with the number of atoms increasing can be circumvented easily. The hybrid system becomes a coupling between a Rydberg superatom and an optomechanical cavity and the coupling strength is enhanced by a factor of square root of the number of atoms in the ensemble. In this system, the perfect OMIT, namely, an ideal OMIT dip with a very narrow window, can be attained when an effect of non-rotating wave approximation (NRWA) is considered. Further, we demonstrate that the term of NRWA plays a key important role in achieving perfect OMIT by comparing the optomechanical spectra obtained with and without NRWA effects. Our results show that in the resolved sideband regime the higher the quality factor of cavity is, the stronger the slow light effect becomes in the window of the perfect OMIT. Particularly, in achieving the ultraslow light, the long lifetime of the Rydberg atom shows its superiority.

Acta Physica Sinica•Jan 1, 2023•3 citations

Optomechanically induced transparency in multi-cavity optomechanical system with and without one two-level atom

Amjad Sohail, Yang Zhang, Jun Zhang +1 more

We analytically study the optomechanically induced transparency (OMIT) in the N-cavity system with the Nth cavity driven by pump, probing laser fields and the 1st cavity coupled to mechanical oscillator. We also consider that one atom could be trapped in the ith cavity. Instead of only illustrating the OMIT in such a system, we are interested in how the number of OMIT windows is influenced by the cavities and the atom and what roles the atom could play in different cavities. In the resolved sideband regime, we find that, the number of cavities precisely determines the maximal number of OMIT windows. It is interesting that, when the two-level atom is trapped in the even-labeled cavity, the central absorptive peak (odd N) or dip (even N) is split and forms an extra OMIT window, but if the atom is trapped in the odd-labeled cavity, the central absorptive peak (odd N) or dip (even N) is only broadened and thus changes the width of the OMIT windows rather than induces an extra window.

arXiv:1606.05866•Scientific Reports•Jun 28, 2016•48 citations
Optomechanically induced transparency (OMIT) is usually modeled and studied in the resolved-sideband regime, but many compact microcavity platforms operate in the unresolved-sideband limit (κ≫Ωm)(κ\gg Ω_m)(κ≫Ωm​). Here we investigate OMIT in this regime using a tunable fiber-based Fabry-Perot microcavity coupled to a suspended hexagonal boron nitride (hBN) drum resonator in a membrane-in-the-middle geometry. The system achieves a large single-photon coupling rate of g0/2π∼180g_0/2π\sim 180g0​/2π∼180 kHz and exhibits strong radiation-pressure backaction. By measuring OMIT spectra as a function of pump power and cavity detuning, we observe a crossover from a transparency-like dip to a gain feature in the reflected response. These maps are quantitatively reproduced by the full linearized optomechanical response, demonstrating the breakdown of the standard rotating-wave approximation used in the resolved-sideband limit. Finally, we drive the system into a nonlinear regime to generate optomechanical frequency combs. These results establish hBN fiber-cavities as a versatile architecture for unresolved-sideband optomechanics, nonlinear dynamics, and hybrid device integration.
Conventional membrane-in-the-middle (MIM) optomechanical systems offer limited control over the optical linewidth, which can limit their performance when operating in the unresolved-sideband regime. We investigate cavity optomechanics with a photonic-crystal Fano membrane placed at the center of a Fabry-Pérot (FP) cavity. In contrast to a conventional dielectric membrane, the photonic-crystal membrane supports a localized optical resonance, which hybridizes with the cavity field and enables spectral engineering of the relevant optical modes. Besides the usual dispersive optomechanical coupling associated with cavity-length changes, the membrane motion also modifies the Fano-mode resonance and its hybridization with the cavity field. We consider two limits set by the membrane reflectivity: a transparent-membrane regime with a single FP-like mode, and a reflective-membrane regime with two coupled subcavity modes. In the latter case, only the symmetric cavity mode hybridizes with the Fano mode, while the antisymmetric mode remains decoupled. Using quantum Langevin equations together with a transfer-matrix description of the optical scattering problem, we show that the Fano-induced hybridization can generate narrow optical normal modes that remain efficiently accessible to the external drive for experimentally realistic parameters. These modes can provide effective sideband resolution and enable ground-state cooling of the membrane motion even when the bare cavity is in the unresolved-sideband regime. Our results establish Fano MIM systems as a promising platform for spectral and optomechanical engineering.
We propose a novel technique of generating multiple optomechanically induced transparency (OMIT) of a weak probe field in hybrid optomechanical system. This system consists of a cigar-shaped Bose–Einstein condensate (BEC), trapped inside each high finesse Fabry-Pérot cavity. In the resolved sideband regime, the analytic solutions of the absorption and the dispersion spectrum are given. The tunneling strength of the two resonators and the coupling parameters of the each BEC in combination with the cavity field have the appearance of three distinct OMIT windows in the absorption spectrum. Furthermore, whether there is BEC in each cavity is a key factor in the number of OMIT windows determination. The technique presented may have potential applications in quantum engineering and quantum information networks.
Intrinsic damping rate and quality factor (QQQ) are key parameters in optomechanical systems. However, in high-Q devices, their measurement is often challenging because probe-induced dynamical backaction (DBA) and the need to resolve and accurately track the mechanical resonance limit the performance of state-of-the-art techniques. Here, we introduce an all-optical ringdown method in the unresolved-sideband regime that exploits the nonlinear, time-averaged optical response induced by strong mechanical motion. We derive an analytical model of the time-averaged optical cavity response probed by a weak frequency-scanning laser. During the evolution of the mechanical oscillator, the excited motion modulates the Lorentzian lineshape into a double-horned profile whose peak separation enables an accurate estimation of the modulation amplitude. Tracking this response during the mechanical ringdown allows the intrinsic damping rate to be determined without resolving the mechanical oscillation. We apply the method to a density-modulated phononic crystal membrane placed inside a high-finesse cavity and obtain mechanical quality factors consistent with independent measurements on the same platform. Our method requires a minimal optical setup, while offering an in situ diagnostic and reduced impact from probe-induced DBA and robustness against measurement noise. Finally, the model can describe other resonant systems dispersively coupled to coherent frequency modulations, providing new insights and measurement strategies that expand beyond the optomechanical platform.
High-overtone bulk acoustic wave resonators (HBARs) promise advanced phononics, yet achieving nonlinearity remains challenging. We demonstrate a radiation-pressure-type parametric interaction between GHz HBARs and low-frequency flexural modes in a suspended silicon nitride membrane, where mechanical displacement modulates the external dissipation rate to enable dissipative acousto-mechanical coupling. Benefiting from the high quality factor, the system enters the resolved-sideband regime at room temperature, yielding acousto-mechanically induced transparency. We observe tunable Kerr nonlinearity and generate coherent HBAR frequency combs via two-tone driving. Notably, our dissipative coupling strength is 20 times larger than the dispersive coupling, the highest ratio among reported hybrid dissipative-dispersive coupling systems, resulting in the experimental observation of amplification in the reflection spectra under red-sideband driving. The ability to interface dense HBAR modes with a common mechanical resonator provides a scalable on-chip platform for multimode phononic information processing, with quantum phononics potentially achievable at sub-Kelvin temperatures.
Rydberg atoms have attracted considerable attention due to their several singular properties, such as strong long-range interactions, extremely long lifetimes, and very large polarizability. These characteristics make Rydberg atoms a good candidates for cavity quantum electrodynamics, quantum information, and many-body physics. Recently, the study of optomechanics has become a rapidly developing field due to its important applications in cooling of mechanical resonators, implementing precision measurements, slowing light, and preparing quantum entanglement. Obviously, optomechanical systems pave the way for quantum information processing and quantum communication. Specially, there is significant interest in quantum optomechanics due to its high compatibility that can be combined, to build hybrid systems for certain purposes, with the ultracold atoms, a superconducting single electron transistor, a magnetostrictive actuation, a charged oscillator resonator, etc. In this work, we investigate the optomechanically induced transparency (OMIT) and the resulting effect of slow light in a hybrid system composed of a Rydberg atomic ensemble embedded inside a simple optomechanical cavity. As a typical effect of destructive quantum interference, OMIT is widely used in quantum optics and quantum information processing. Based on the Rydberg blockade effect, a Rydberg atomic ensemble in the same blockade region embedded inside an optomechanical cavity can be regarded as a superatom that contains only a single Rydberg excitation. Therefore, the problem of exponentially increasing system size with the number of atoms increasing can be circumvented easily. The hybrid system becomes a coupling between a Rydberg superatom and an optomechanical cavity and the coupling strength is enhanced by a factor of square root of the number of atoms in the ensemble. In this system, the perfect OMIT, namely, an ideal OMIT dip with a very narrow window, can be attained when an effect of non-rotating wave approximation (NRWA) is considered. Further, we demonstrate that the term of NRWA plays a key important role in achieving perfect OMIT by comparing the optomechanical spectra obtained with and without NRWA effects. Our results show that in the resolved sideband regime the higher the quality factor of cavity is, the stronger the slow light effect becomes in the window of the perfect OMIT. Particularly, in achieving the ultraslow light, the long lifetime of the Rydberg atom shows its superiority.
We analytically study the optomechanically induced transparency (OMIT) in the N-cavity system with the Nth cavity driven by pump, probing laser fields and the 1st cavity coupled to mechanical oscillator. We also consider that one atom could be trapped in the ith cavity. Instead of only illustrating the OMIT in such a system, we are interested in how the number of OMIT windows is influenced by the cavities and the atom and what roles the atom could play in different cavities. In the resolved sideband regime, we find that, the number of cavities precisely determines the maximal number of OMIT windows. It is interesting that, when the two-level atom is trapped in the even-labeled cavity, the central absorptive peak (odd N) or dip (even N) is split and forms an extra OMIT window, but if the atom is trapped in the odd-labeled cavity, the central absorptive peak (odd N) or dip (even N) is only broadened and thus changes the width of the OMIT windows rather than induces an extra window.