Vibrational strong coupling(VSC)provides a promising way towards not only enhanced control of infrared light but also reshaping of molecular properties,which opens up unprecedented opportunities in ultrasensitive infr...Vibrational strong coupling(VSC)provides a promising way towards not only enhanced control of infrared light but also reshaping of molecular properties,which opens up unprecedented opportunities in ultrasensitive infrared spectroscopy,modification of chemical reactions,and exploration of nonlinear quantum effects.Surface plasmon resonance,excited on simple plasmonic resonators in the infrared,has been demonstrated as a means to realize VSC,but suffers from either limited quality factor for realizing large Rabi splitting or poor reconfigurability for precise detuning control.Here we propose and experimentally demonstrate,for the first time,an on-chip plasmonic resonator based on degeneracy breaking of Wood’s anomaly for VSC.Leveraging the low damping rate of the surface state induced by this degeneracy breaking,we achieve a plasmonic resonance with a high-Q factor exceeding~110,resulting in a Rabi splitting up to~112 cm^(-1) with a subwavelength molecular layer.Additionally,the dispersion of the surface state allows for precise control over VSC detuning by simply adjusting the incident angle of excitation light,even in the absence of photons,enabling a broad detuning range up to 300 cm^(-1).These experimental results align well with our analytical model and numerical simulation.This work provides a promising integrated platform for VSC,with various potential applications in on-chip spectroscopy,polariton chemistry,and polariton devices.展开更多
Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves....Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.展开更多
By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic f...By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic field and confinement strength, the magnetopolaron binding energy of QD and QW in the ground state and in the excited state is enhanced. The limiting results of bulk type and strict two dimensional type are obtained.展开更多
By using the variational method of Pekar type, the ground state and the first excited state of the strong coupling magnetopolaron in cylinder shape quantum dot are considered. The results show that, with the increasi...By using the variational method of Pekar type, the ground state and the first excited state of the strong coupling magnetopolaron in cylinder shape quantum dot are considered. The results show that, with the increasing cyclotron frequency and the confinement strength, the magnetopolaron binding energies in both the ground state and the excited state, and the resonance frequency of magnetopolaron are enhanced. The limiting case of the bulk and strict one dimensional type is also discussed.展开更多
Cavity optomechanical systems provide powerful platforms to manipulate photons and phonons, open potential ap- plications for modern optical communications and precise measurements. With the refrigeration and ground-s...Cavity optomechanical systems provide powerful platforms to manipulate photons and phonons, open potential ap- plications for modern optical communications and precise measurements. With the refrigeration and ground-state cooling technologies, studies of cavity optomechanics are making significant progress towards the quantum regime including non- classical state preparation, quantum state tomography, quantum information processing, and future quantum internet. With further research, it is found that abundant physical phenomena and important applications in both classical and quan- tum regimes appeal as they have a strong optomechanical nonlinearity, which essentially depends on the single-photon optomechanical coupling strength. Thus, engineering the optomechanical interactions and improving the single-photon optomechanical coupling strength become very important subjects. In this article, we first review several mechanisms, theoretically proposed for enhancing optomechanical coupling. Then, we review the experimental progresses on enhancing optomechanical coupling by optimizing its structure and fabrication process. Finally, we review how to use novel structures and materials to enhance the optomechanical coupling strength. The manipulations of the photons and phonons at the level of strong optomechanical coupling are also summarized.展开更多
We propose a terahertz hybrid metamaterial composed of subwavelength metallic slits and graphene plasmonic ribbons for sensing application.This special design can cause the interaction between the plasmon resonances o...We propose a terahertz hybrid metamaterial composed of subwavelength metallic slits and graphene plasmonic ribbons for sensing application.This special design can cause the interaction between the plasmon resonances of the metallic slits and graphene ribbons,giving rise to a strong coupling effect and Rabi splitting.Intricate balancing in the strong coupling region can be perturbed by the carrier concentration of graphene,which is subject to the analyte on its surface.Thereby,the detection of analyte can be reflected as a frequency shift of resonance in terahertz transmission spectra.The result shows that this sensor can achieve a theoretical detection limit of 325 electrons or holes per square micrometer.Meanwhile,it also works well as a refractive index sensor with the frequency sensitivity of 485 GHz/RIU.Our results may contribute to design of ultra-micro terahertz sensors.展开更多
The circular dichroism(CD) signal of a molecule is usually weak,however,a strong CD signal in optical spectrum is desirable because of its wide range of applications in biosensing,chiral photo detection,and chiral cat...The circular dichroism(CD) signal of a molecule is usually weak,however,a strong CD signal in optical spectrum is desirable because of its wide range of applications in biosensing,chiral photo detection,and chiral catalysis.In this work,we show that a strong chiral response can be obtained in a hybridized system consisting of an artificial chiral molecule and a nanorod in the strong coupling regime.The artificial chiral molecule is composed of six quantum dots in a helix assembly,and its CD signal arises from internal Coulomb interactions between quantum dots.The CD signal of the hybridized system is highly dependent on the Coulomb interactions and the strong coupling progress through the electromagnetic interactions.We use the coupled oscillator model to analyze strong coupling phenomenon and address that the strong coupling progress can amplify the CD signal.This work provides a scenario for designing new plasmonic nanostructures with a strong chiral optical response.展开更多
In this paper, we present a simple theoretical approach to calculate the multiple ionization of big atoms and molecules induced by very high-q fast projectiles in a strong coupling regime （q/v 〉 1）. The results obt...In this paper, we present a simple theoretical approach to calculate the multiple ionization of big atoms and molecules induced by very high-q fast projectiles in a strong coupling regime （q/v 〉 1）. The results obtained from this approach are in excellent agreement with the available experimental data. A probable scenario of molecular multiple ionization by fast and very high-q projectiles is discussed. The very small computational time required here and the good agreement with the existing experimental data make it a good candidate for studying the multiple ionization of complex molecules under high linear energy transfers.展开更多
Metallic nanostructures can support the strongly confined interface waves:surface plasmon polaritons(SPPs).SPPs have recently been used in a variety of applications due to their abilities to guide light in the scale o...Metallic nanostructures can support the strongly confined interface waves:surface plasmon polaritons(SPPs).SPPs have recently been used in a variety of applications due to their abilities to guide light in the scale of na-nometer.Whereas,intrinsic weak optical nonlinearities and short propagation lengths of SPPs hinder their applica-tions in novel active plasmonic devices.One promising solution is to couple SPPs to nonlinear optical resonances,such as excitons(Xs)in molecular or semiconducting nanostructures.Consequently,hybrid nanostructures containing J-aggregate molecules and metallic nanostructures have attracted considerable interest.In these systems,vacuum field fluctuations lead to a coherent ex-change of energy between ensembles of excitons and plasmons and the formation of new hybrid polariton states.Strong coupling between Xs and SPPs enables an efficient transfer of the strong optical nonlinearities of the excitonic emitters to the passive plasmonic nanostructures on the ultrashort time scale of femtosecond.展开更多
We theoretically investigate the strong coupling in silver-molecular J-aggregates-silver structure sandwiched between two dielectric media by using classical methods. Fresnel equations are employed to solve our propos...We theoretically investigate the strong coupling in silver-molecular J-aggregates-silver structure sandwiched between two dielectric media by using classical methods. Fresnel equations are employed to solve our proposed structure. The results show that both the reflection and transmission spectra show a Rabi splitting-like line shape, revealing the strong coupling phenomenon. Furthermore, the radiative angle versus incident wavelength exhibits a Fano line shape. The strong coupling phenomenon can be well tuned by controlling the surface plasmon excitation, such as the incident angle and the thickness of the silver films. Our structure has potential applications in quantum networks, optical switches, and so on.展开更多
Fluctuation theorems have been applied successfully to any system away from thermal equilibrium,which are helpful for understanding the thermodynamic state evolution.We investigate fluctuation theorems for strong coup...Fluctuation theorems have been applied successfully to any system away from thermal equilibrium,which are helpful for understanding the thermodynamic state evolution.We investigate fluctuation theorems for strong coupling between a system and its reservoir,by path-dependent definition of work and heat satisfying the first law of thermodynamics.We present the fluctuation theorems for two kinds of entropy productions.One is the informational entropy production,which is always non-negative and can be employed in either strong or weak coupling systems.The other is the thermodynamic entropy production,which differs from the informational entropy production at strong coupling by the effects regarding the reservoir.We find that,it is the negative work on the reservoir,rather than the nonequilibrium of the thermal reservoir,which invalidates the thermodynamic entropy production at strong coupling.Our results indicate that the effects from the reservoir are essential to understanding thermodynamic processes at strong coupling.展开更多
Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum g...Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum galactic rotation velocity by the simple relation , where is the velocity, at which the difference between galactic rotation velocity and Thomas precession is equal, and α is Sommerfeld’s constant. The result is in excellent agreement with the value of α<sub>s</sub> = 0.1170 ± 0.0019, recently measured and verified via QCE analysis by CERN researchers. One can formulate a reciprocity relation, connecting α<sub>s</sub> with the circle constant: . It is the merit of Preston Guynn to derive the Milky Way maximum value of the galactic rotation velocity β<sub>g</sub>, pointing to its “extremely important role in all physics”. The mass (energy) constituents of the Universe follow a golden mean hierarchy and can simply be related to the maximum of Guynn’s difference velocity respectively to α<sub>s</sub>(m<sub>z</sub>), therewith excellently confirming Bouchet’s WMAP data analysis. We conclude once more that the golden mean concept is the leading one of nature.展开更多
In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work in the strong atom-field coupling regime wherein the rotating wave approximation(RWA)is no longer vali...In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work in the strong atom-field coupling regime wherein the rotating wave approximation(RWA)is no longer valid.To achieve the purpose,a scheme consisting of a qubit interacting with a single-mode quantized field is described via the Rabi model(counter rotation terms are taken into account).Our first aim is to teleport an unknown atomic state of a qubit(which interacts with the quantized field in a cavity)to a second qubit(exists in another distant cavity field),beyond the RWA and without the Bell-state measurement method.In the continuation,in a similar way,we teleport an unknown state of a single-mode field too.In fact,it is shown that,in this regime,after applying some particular conditions,containing the interaction time of atom-field in the cavities,adjusting the involved frequencies,as well as the atom-field coupling in the model,if a proper measurement is performed on the state of the first qubit(the related field in the cavity),the unknown states of the qubit(field)can be teleported from the first qubit(cavity field)to the second qubit(cavity field),appropriately.We show that in both considered cases,the teleportation protocol is successfully performed with the maximum possible fidelity,1,and the acceptable success probability,0.25.展开更多
The quantum hydrodynamic model for electrons and ions and the generalized hydrodynamic model for the strongly coupled dust particles are proposed in the strongly coupled quantum dusty plasma, where the combined quantu...The quantum hydrodynamic model for electrons and ions and the generalized hydrodynamic model for the strongly coupled dust particles are proposed in the strongly coupled quantum dusty plasma, where the combined quantum effects of quantum diffraction, quantum statistic pressure,as well as electron exchange and correlation effects are all considered in the quantum hydrodynamic model. The shear and bulk viscosity effects are included in the viscoelastic relaxation, which leads to the decay of the dust-ion-acoustic waves. The approximate time-dependent solitary solution is obtained by the momentum conservation law in the presence of viscosity.展开更多
Surface plasmon polaritons(SPPs)on metal surfaces excited by p-polarized light have long been a crucial method for achieving lightmatter interactions due to their small mode-field volumes and strong optical localizati...Surface plasmon polaritons(SPPs)on metal surfaces excited by p-polarized light have long been a crucial method for achieving lightmatter interactions due to their small mode-field volumes and strong optical localization properties.However,the significant losses generated in metals greatly limit the intensity of the SPPs and their potential application scenarios.In this paper,we leverage the high refractive index properties of two-dimensional(2D)transition metal dichalcogenides(TMDCs)to generate transverse-electric(TE)polarized waves excited by s-polarized light on the surface of gold nanofilms by accurately controlling the number of the TMDC layers and the spatial refractive index variations with the structure.Unlike the SPPs excited by p-polarized light,the TE surface waves on the surface of the gold film exhibit low loss and high quality factor(Q factor).Moreover,the difference in refractive index causes the TE surface waves to be electromagnetically separated in space,lifting the electric field component in the excited TE surface waves from the surface of the metal film into the TMDCs,thereby minimizing the ohmic loss in the metal and enabling strong coupling between the TE surface waves and the two-exciton states(A-exciton and B-exciton)in the TMDCs.Experimental results demonstrated the strong coupling of TE waves with double excitons(A-exciton and B-exciton)in multilayer MoS_(2) by exciting the Au/MoS_(2) heterostructure using a KretschmannRaether configuration,showing ultrahigh Rabi splitting up to about 310 meV.Furthermore,the number of MoS_(2) layers can be accurately determined by measuring the redshift of the Rabi splitting peak of the strong coupling spectra in the Au/MoS_(2) heterostructure.Our findings open a new avenue for manipulating strong exciton-photon coupling in 2D materials and offer a novel approach for accurately characterizing the thickness of TMDCs.展开更多
In this study,we employed the heavy quark expansion model with the kinetic scheme to evaluate os(m^(2)_(c)),the strong coupling constant at the chamn quark mass me,using data on inclusive semileptonic decays of charme...In this study,we employed the heavy quark expansion model with the kinetic scheme to evaluate os(m^(2)_(c)),the strong coupling constant at the chamn quark mass me,using data on inclusive semileptonic decays of charmed mesons.Using the experimental values of the semileptonic decay widths of the D^(0)and the D^(+),the value of ars(m^(2))was determined to be 0.445±0.009±0.114,where the first uncertainty is experimental and the second is systematic.This value of a,(m^(2))is in good agreement with the value of ar,(m^(2)_(c))which calculated by running as(m^(2))athe 20 bo-son mass mz with the renormalization group evolution equation.In addition,the values of a_(s)(m^(2)_(c))obtained individu-ally from each of the D,D+,and D5 mesons were consistent,as they were of the same origin.展开更多
Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmo...Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall volume.Additionally,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter interactions.As a result,strong plasmon-exciton coupling has been reported by introducing a single metallic cavity.However,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic resonance.Here,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton coupling.The demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or thickness.The calculated Rabi splitting of Au-MoSe_2 and Au-WSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me V.These plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature.展开更多
Strong light-matter interactions in two-dimensional transition metal dichalcogenides(TMDCs)with robust spin-valley degrees of freedom open up the prospect of valleytronic devices.A thorough understanding on the dynami...Strong light-matter interactions in two-dimensional transition metal dichalcogenides(TMDCs)with robust spin-valley degrees of freedom open up the prospect of valleytronic devices.A thorough understanding on the dynamics of the valley polarizations in the strong coupling regime is urgently required.Here,multiple polarized TMDCs-SPPs hybrid systems were constructed by combining monolayer WS_(2)flakes to linear,circular,and spiral Ag gratings,resulting in linear and circular polarized modula-tion on the coherent hybrid states,respectively.Particularly,valley polaritons can be tailored asymmetrically by chiral strong coupling regime.Furthermore,the dynamics of the polarized polaritons were directly analyzed by transient absorption(TA)measure-ment.Both of the linear and circular polarization difference in the TA spectra can be retained for a remarkable long time,leading to a polarized PL even at room tempera-ture.More importantly,in the chiral strong coupled WS_(2)-spiral Ag grating devices,the mechanism of the asymmetrical valley-polarized PL(p_(σ+)=14.9%and p_(σ-)=10.8%)is proved by the opposite valley polarization dynamics in the circularly polarized TA spectra.The multiple polarization modulation in monolayer TMDCs-SPPs strong coupling devices could provide a viable route toward multiple polarization polaritonic devices.展开更多
Electric transport and scanning tunneling spectrum(STS)have been investigated on polycrystalline samples of the new superconductor Bi4O4S3.A weak insulating behavior in the resistive curve has been induced in the norm...Electric transport and scanning tunneling spectrum(STS)have been investigated on polycrystalline samples of the new superconductor Bi4O4S3.A weak insulating behavior in the resistive curve has been induced in the normal state when the superconductivity is suppressed by applying a magnetic field.Interestingly,a kink appears on the temperature dependence of resistivity near 4 K at all high magnetic fields above 1 T when the bulk superconductivity is completely suppressed.This kink associated with the upper critical field as well as the wide range of excess conductance at low fields and high temperatures is explained as the possible evidence of strong superconducting fluctuation.From the tunneling spectra,a superconducting gap of about 3 meV is frequently observed yielding a ratio of 2Δ/kB TC^16.6.This value is much larger than the one predicted by the BCS theory in the weak coupling regime(2Δ/kB TC^3.53),which suggests the strong coupling superconductivity in the present system.Furthermore,the gapped feature persists on the spectra until 14 K in the STS measurement,which suggests a prominent fluctuation region of superconductivity.Such a superconducting fluctuation can survive at very high magnetic fields,which are far beyond the critical fields for bulk superconductivity as inferred both from electric transport and tunneling measurements.展开更多
In recent years,quantum nanophotonics has forged a rich nexus of nanotechnology with photonic quantum information processing,offering remarkable prospects for advancing quantum technologies beyond their current techni...In recent years,quantum nanophotonics has forged a rich nexus of nanotechnology with photonic quantum information processing,offering remarkable prospects for advancing quantum technologies beyond their current technical limits in terms of physical compactness,energy efficiency,operation speed,temperature robustness and scalability.In this perspective,we highlight a number of recent studies that reveal the especially compelling potential of nanoplasmonic cavity quantum electrodynamics for driving quantum technologies down to nanoscale spatial and ultrafast temporal regimes,whilst elevating them to ambient temperatures.Our perspective encompasses innovative proposals for quantum plasmonic biosensing,driving ultrafast singlephoton emission and achieving near-field multipartite entanglement in the strong coupling regime,with a notable emphasis on the use of industry-grade devices.We conclude with an outlook emphasizing how the bespoke characteristics and functionalities of plasmonic devices are shaping contemporary research directives in ultrafast and room-temperature quantum nanotechnologies.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2024YFE0105200)the National Nature Science Foundation of China(Grant No.62405284)+2 种基金the Key Research and Development Program of Henan Province(Grant No.241111220600)the JSPS KAKENHI(Grant No.JP20K14785)the Murata Science Foundation.
文摘Vibrational strong coupling(VSC)provides a promising way towards not only enhanced control of infrared light but also reshaping of molecular properties,which opens up unprecedented opportunities in ultrasensitive infrared spectroscopy,modification of chemical reactions,and exploration of nonlinear quantum effects.Surface plasmon resonance,excited on simple plasmonic resonators in the infrared,has been demonstrated as a means to realize VSC,but suffers from either limited quality factor for realizing large Rabi splitting or poor reconfigurability for precise detuning control.Here we propose and experimentally demonstrate,for the first time,an on-chip plasmonic resonator based on degeneracy breaking of Wood’s anomaly for VSC.Leveraging the low damping rate of the surface state induced by this degeneracy breaking,we achieve a plasmonic resonance with a high-Q factor exceeding~110,resulting in a Rabi splitting up to~112 cm^(-1) with a subwavelength molecular layer.Additionally,the dispersion of the surface state allows for precise control over VSC detuning by simply adjusting the incident angle of excitation light,even in the absence of photons,enabling a broad detuning range up to 300 cm^(-1).These experimental results align well with our analytical model and numerical simulation.This work provides a promising integrated platform for VSC,with various potential applications in on-chip spectroscopy,polariton chemistry,and polariton devices.
基金financial supports from National Natural Science Foundation of China(No.61905051)Natural Science Foundation of Heilongjiang Province(No.LH2020F027).
文摘Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.
文摘By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic field and confinement strength, the magnetopolaron binding energy of QD and QW in the ground state and in the excited state is enhanced. The limiting results of bulk type and strict two dimensional type are obtained.
文摘By using the variational method of Pekar type, the ground state and the first excited state of the strong coupling magnetopolaron in cylinder shape quantum dot are considered. The results show that, with the increasing cyclotron frequency and the confinement strength, the magnetopolaron binding energies in both the ground state and the excited state, and the resonance frequency of magnetopolaron are enhanced. The limiting case of the bulk and strict one dimensional type is also discussed.
基金Project supported by the National Basic Research Program of China(Grant No.2014CB921401)the Tsinghua University Initiative Scientific Research Programthe Tsinghua National Laboratory for Information Science and Technology(TNList)Cross-discipline Foundation
文摘Cavity optomechanical systems provide powerful platforms to manipulate photons and phonons, open potential ap- plications for modern optical communications and precise measurements. With the refrigeration and ground-state cooling technologies, studies of cavity optomechanics are making significant progress towards the quantum regime including non- classical state preparation, quantum state tomography, quantum information processing, and future quantum internet. With further research, it is found that abundant physical phenomena and important applications in both classical and quan- tum regimes appeal as they have a strong optomechanical nonlinearity, which essentially depends on the single-photon optomechanical coupling strength. Thus, engineering the optomechanical interactions and improving the single-photon optomechanical coupling strength become very important subjects. In this article, we first review several mechanisms, theoretically proposed for enhancing optomechanical coupling. Then, we review the experimental progresses on enhancing optomechanical coupling by optimizing its structure and fabrication process. Finally, we review how to use novel structures and materials to enhance the optomechanical coupling strength. The manipulations of the photons and phonons at the level of strong optomechanical coupling are also summarized.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61865009,61927813,and 62005168).
文摘We propose a terahertz hybrid metamaterial composed of subwavelength metallic slits and graphene plasmonic ribbons for sensing application.This special design can cause the interaction between the plasmon resonances of the metallic slits and graphene ribbons,giving rise to a strong coupling effect and Rabi splitting.Intricate balancing in the strong coupling region can be perturbed by the carrier concentration of graphene,which is subject to the analyte on its surface.Thereby,the detection of analyte can be reflected as a frequency shift of resonance in terahertz transmission spectra.The result shows that this sensor can achieve a theoretical detection limit of 325 electrons or holes per square micrometer.Meanwhile,it also works well as a refractive index sensor with the frequency sensitivity of 485 GHz/RIU.Our results may contribute to design of ultra-micro terahertz sensors.
基金Project supported by the National Key R&D Program of China(Grant No.2016YFA0301300)the Fundamental Research Funds for the Central Universities,China(Grant No.2019XD-A09)the National Natural Science Foundation of China(Grant No.11574035)。
文摘The circular dichroism(CD) signal of a molecule is usually weak,however,a strong CD signal in optical spectrum is desirable because of its wide range of applications in biosensing,chiral photo detection,and chiral catalysis.In this work,we show that a strong chiral response can be obtained in a hybridized system consisting of an artificial chiral molecule and a nanorod in the strong coupling regime.The artificial chiral molecule is composed of six quantum dots in a helix assembly,and its CD signal arises from internal Coulomb interactions between quantum dots.The CD signal of the hybridized system is highly dependent on the Coulomb interactions and the strong coupling progress through the electromagnetic interactions.We use the coupled oscillator model to analyze strong coupling phenomenon and address that the strong coupling progress can amplify the CD signal.This work provides a scenario for designing new plasmonic nanostructures with a strong chiral optical response.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11174116 and 11175075)
文摘In this paper, we present a simple theoretical approach to calculate the multiple ionization of big atoms and molecules induced by very high-q fast projectiles in a strong coupling regime （q/v 〉 1）. The results obtained from this approach are in excellent agreement with the available experimental data. A probable scenario of molecular multiple ionization by fast and very high-q projectiles is discussed. The very small computational time required here and the good agreement with the existing experimental data make it a good candidate for studying the multiple ionization of complex molecules under high linear energy transfers.
文摘Metallic nanostructures can support the strongly confined interface waves:surface plasmon polaritons(SPPs).SPPs have recently been used in a variety of applications due to their abilities to guide light in the scale of na-nometer.Whereas,intrinsic weak optical nonlinearities and short propagation lengths of SPPs hinder their applica-tions in novel active plasmonic devices.One promising solution is to couple SPPs to nonlinear optical resonances,such as excitons(Xs)in molecular or semiconducting nanostructures.Consequently,hybrid nanostructures containing J-aggregate molecules and metallic nanostructures have attracted considerable interest.In these systems,vacuum field fluctuations lead to a coherent ex-change of energy between ensembles of excitons and plasmons and the formation of new hybrid polariton states.Strong coupling between Xs and SPPs enables an efficient transfer of the strong optical nonlinearities of the excitonic emitters to the passive plasmonic nanostructures on the ultrashort time scale of femtosecond.
基金Project supported by the Science Fund from the Ministry of Science and Technology of China(Grant No.2016YFA0301300)the Fundamental Research Funds for the Central Universities,China
文摘We theoretically investigate the strong coupling in silver-molecular J-aggregates-silver structure sandwiched between two dielectric media by using classical methods. Fresnel equations are employed to solve our proposed structure. The results show that both the reflection and transmission spectra show a Rabi splitting-like line shape, revealing the strong coupling phenomenon. Furthermore, the radiative angle versus incident wavelength exhibits a Fano line shape. The strong coupling phenomenon can be well tuned by controlling the surface plasmon excitation, such as the incident angle and the thickness of the silver films. Our structure has potential applications in quantum networks, optical switches, and so on.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11674360,11734018,11835011,and 11965012)the Applied Basic Research Project of Yunnan Province,China(Grant No.2017FB004)
文摘Fluctuation theorems have been applied successfully to any system away from thermal equilibrium,which are helpful for understanding the thermodynamic state evolution.We investigate fluctuation theorems for strong coupling between a system and its reservoir,by path-dependent definition of work and heat satisfying the first law of thermodynamics.We present the fluctuation theorems for two kinds of entropy productions.One is the informational entropy production,which is always non-negative and can be employed in either strong or weak coupling systems.The other is the thermodynamic entropy production,which differs from the informational entropy production at strong coupling by the effects regarding the reservoir.We find that,it is the negative work on the reservoir,rather than the nonequilibrium of the thermal reservoir,which invalidates the thermodynamic entropy production at strong coupling.Our results indicate that the effects from the reservoir are essential to understanding thermodynamic processes at strong coupling.
文摘Some fundamental physical quantities need an alternative description. We derive the word average value of interaction coupling constant α<sub>s</sub>(m<sub>z</sub>) from the observed maximum galactic rotation velocity by the simple relation , where is the velocity, at which the difference between galactic rotation velocity and Thomas precession is equal, and α is Sommerfeld’s constant. The result is in excellent agreement with the value of α<sub>s</sub> = 0.1170 ± 0.0019, recently measured and verified via QCE analysis by CERN researchers. One can formulate a reciprocity relation, connecting α<sub>s</sub> with the circle constant: . It is the merit of Preston Guynn to derive the Milky Way maximum value of the galactic rotation velocity β<sub>g</sub>, pointing to its “extremely important role in all physics”. The mass (energy) constituents of the Universe follow a golden mean hierarchy and can simply be related to the maximum of Guynn’s difference velocity respectively to α<sub>s</sub>(m<sub>z</sub>), therewith excellently confirming Bouchet’s WMAP data analysis. We conclude once more that the golden mean concept is the leading one of nature.
文摘In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work in the strong atom-field coupling regime wherein the rotating wave approximation(RWA)is no longer valid.To achieve the purpose,a scheme consisting of a qubit interacting with a single-mode quantized field is described via the Rabi model(counter rotation terms are taken into account).Our first aim is to teleport an unknown atomic state of a qubit(which interacts with the quantized field in a cavity)to a second qubit(exists in another distant cavity field),beyond the RWA and without the Bell-state measurement method.In the continuation,in a similar way,we teleport an unknown state of a single-mode field too.In fact,it is shown that,in this regime,after applying some particular conditions,containing the interaction time of atom-field in the cavities,adjusting the involved frequencies,as well as the atom-field coupling in the model,if a proper measurement is performed on the state of the first qubit(the related field in the cavity),the unknown states of the qubit(field)can be teleported from the first qubit(cavity field)to the second qubit(cavity field),appropriately.We show that in both considered cases,the teleportation protocol is successfully performed with the maximum possible fidelity,1,and the acceptable success probability,0.25.
基金supported by the National Natural Science Foundation of China (NSFC) (Grant No. 11974043)the Fundamental Research Funds for the Central Universities (Grant No. FRF-BR-19-002B)。
文摘The quantum hydrodynamic model for electrons and ions and the generalized hydrodynamic model for the strongly coupled dust particles are proposed in the strongly coupled quantum dusty plasma, where the combined quantum effects of quantum diffraction, quantum statistic pressure,as well as electron exchange and correlation effects are all considered in the quantum hydrodynamic model. The shear and bulk viscosity effects are included in the viscoelastic relaxation, which leads to the decay of the dust-ion-acoustic waves. The approximate time-dependent solitary solution is obtained by the momentum conservation law in the presence of viscosity.
基金Natural Science Foundation of Guangdong Province(2025A1515012259)National Natural Science Foundation of China(12274148,12374347,12174123).
文摘Surface plasmon polaritons(SPPs)on metal surfaces excited by p-polarized light have long been a crucial method for achieving lightmatter interactions due to their small mode-field volumes and strong optical localization properties.However,the significant losses generated in metals greatly limit the intensity of the SPPs and their potential application scenarios.In this paper,we leverage the high refractive index properties of two-dimensional(2D)transition metal dichalcogenides(TMDCs)to generate transverse-electric(TE)polarized waves excited by s-polarized light on the surface of gold nanofilms by accurately controlling the number of the TMDC layers and the spatial refractive index variations with the structure.Unlike the SPPs excited by p-polarized light,the TE surface waves on the surface of the gold film exhibit low loss and high quality factor(Q factor).Moreover,the difference in refractive index causes the TE surface waves to be electromagnetically separated in space,lifting the electric field component in the excited TE surface waves from the surface of the metal film into the TMDCs,thereby minimizing the ohmic loss in the metal and enabling strong coupling between the TE surface waves and the two-exciton states(A-exciton and B-exciton)in the TMDCs.Experimental results demonstrated the strong coupling of TE waves with double excitons(A-exciton and B-exciton)in multilayer MoS_(2) by exciting the Au/MoS_(2) heterostructure using a KretschmannRaether configuration,showing ultrahigh Rabi splitting up to about 310 meV.Furthermore,the number of MoS_(2) layers can be accurately determined by measuring the redshift of the Rabi splitting peak of the strong coupling spectra in the Au/MoS_(2) heterostructure.Our findings open a new avenue for manipulating strong exciton-photon coupling in 2D materials and offer a novel approach for accurately characterizing the thickness of TMDCs.
基金Supported by the National Natural Science Foundation of China(12247119,12042507)。
文摘In this study,we employed the heavy quark expansion model with the kinetic scheme to evaluate os(m^(2)_(c)),the strong coupling constant at the chamn quark mass me,using data on inclusive semileptonic decays of charmed mesons.Using the experimental values of the semileptonic decay widths of the D^(0)and the D^(+),the value of ars(m^(2))was determined to be 0.445±0.009±0.114,where the first uncertainty is experimental and the second is systematic.This value of a,(m^(2))is in good agreement with the value of ar,(m^(2)_(c))which calculated by running as(m^(2))athe 20 bo-son mass mz with the renormalization group evolution equation.In addition,the values of a_(s)(m^(2)_(c))obtained individu-ally from each of the D,D+,and D5 mesons were consistent,as they were of the same origin.
基金supported by the Australian Research Council (DP200101353)。
文摘Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall volume.Additionally,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter interactions.As a result,strong plasmon-exciton coupling has been reported by introducing a single metallic cavity.However,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic resonance.Here,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton coupling.The demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or thickness.The calculated Rabi splitting of Au-MoSe_2 and Au-WSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me V.These plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature.
基金supported by the National Key Research and Development Program of China and the National Natural Science Foundation of China(NSFC)under Grants 21903035,22073037,21773087,12074141,61960206003Jilin Provincial Science and Technology Development Project(20210509038RQ).
文摘Strong light-matter interactions in two-dimensional transition metal dichalcogenides(TMDCs)with robust spin-valley degrees of freedom open up the prospect of valleytronic devices.A thorough understanding on the dynamics of the valley polarizations in the strong coupling regime is urgently required.Here,multiple polarized TMDCs-SPPs hybrid systems were constructed by combining monolayer WS_(2)flakes to linear,circular,and spiral Ag gratings,resulting in linear and circular polarized modula-tion on the coherent hybrid states,respectively.Particularly,valley polaritons can be tailored asymmetrically by chiral strong coupling regime.Furthermore,the dynamics of the polarized polaritons were directly analyzed by transient absorption(TA)measure-ment.Both of the linear and circular polarization difference in the TA spectra can be retained for a remarkable long time,leading to a polarized PL even at room tempera-ture.More importantly,in the chiral strong coupled WS_(2)-spiral Ag grating devices,the mechanism of the asymmetrical valley-polarized PL(p_(σ+)=14.9%and p_(σ-)=10.8%)is proved by the opposite valley polarization dynamics in the circularly polarized TA spectra.The multiple polarization modulation in monolayer TMDCs-SPPs strong coupling devices could provide a viable route toward multiple polarization polaritonic devices.
基金supported by the 973 Project of the Ministry of Science and Technology of China (Grant Nos. 2011CBA001002, 2010CB923002, and 2012CB821403)the National Natural Science Foundation of China (Grant No. 11034011)+1 种基金the Program for New Century Excellent Talents in University (Grant No. NCET-12-0255)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Electric transport and scanning tunneling spectrum(STS)have been investigated on polycrystalline samples of the new superconductor Bi4O4S3.A weak insulating behavior in the resistive curve has been induced in the normal state when the superconductivity is suppressed by applying a magnetic field.Interestingly,a kink appears on the temperature dependence of resistivity near 4 K at all high magnetic fields above 1 T when the bulk superconductivity is completely suppressed.This kink associated with the upper critical field as well as the wide range of excess conductance at low fields and high temperatures is explained as the possible evidence of strong superconducting fluctuation.From the tunneling spectra,a superconducting gap of about 3 meV is frequently observed yielding a ratio of 2Δ/kB TC^16.6.This value is much larger than the one predicted by the BCS theory in the weak coupling regime(2Δ/kB TC^3.53),which suggests the strong coupling superconductivity in the present system.Furthermore,the gapped feature persists on the spectra until 14 K in the STS measurement,which suggests a prominent fluctuation region of superconductivity.Such a superconducting fluctuation can survive at very high magnetic fields,which are far beyond the critical fields for bulk superconductivity as inferred both from electric transport and tunneling measurements.
基金funding from Science Foundation Ireland via Grant No.18/RP/6236.
文摘In recent years,quantum nanophotonics has forged a rich nexus of nanotechnology with photonic quantum information processing,offering remarkable prospects for advancing quantum technologies beyond their current technical limits in terms of physical compactness,energy efficiency,operation speed,temperature robustness and scalability.In this perspective,we highlight a number of recent studies that reveal the especially compelling potential of nanoplasmonic cavity quantum electrodynamics for driving quantum technologies down to nanoscale spatial and ultrafast temporal regimes,whilst elevating them to ambient temperatures.Our perspective encompasses innovative proposals for quantum plasmonic biosensing,driving ultrafast singlephoton emission and achieving near-field multipartite entanglement in the strong coupling regime,with a notable emphasis on the use of industry-grade devices.We conclude with an outlook emphasizing how the bespoke characteristics and functionalities of plasmonic devices are shaping contemporary research directives in ultrafast and room-temperature quantum nanotechnologies.
