This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analys...This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analyses,strong coupling between excitons of perovskite and cavity photons is revealed,indicating the formation of polaritons in the perovskite microcavity.Besides,it is found that an external optical Stark pulse can induce energy shifts of excitons proportional to the pulse intensity,which modifies the dispersion characteristics of the polaritons.展开更多
The low-temperature (T = 2 K) exciton-polariton luminescence (EPL) spectra in the vicinity of the exciton-resonance frequency An=1 for CdS-type crystals have been theoretically and experimentally investigated with all...The low-temperature (T = 2 K) exciton-polariton luminescence (EPL) spectra in the vicinity of the exciton-resonance frequency An=1 for CdS-type crystals have been theoretically and experimentally investigated with allowance for the mechanical exciton decay . The results of the numerical calculations of the partial and interference contributions of the bulk and radiative surface spectral modes to the EPL in the geometry of additional s- and p-polarized waves emitted into vacuum are analyzed. It is shown that the contributions of purely longitudinal excitons and their interference with polaritons of the upper dispersion branch near the longitudinal frequency ωL to the EPL are small (∼10% - 30%);nevertheless, they must be taken into account to obtain quantitative agreement with experimental data. Specifically these contributions are responsible for the formation of an additional line (along with the fundamental AT line) in the case of oblique incidence of radiation.展开更多
Nano Lett.,18,3335-3343(2018)Microcavity exciton-polariton is a Bosonic quasi-particle of half-matter and half-light formed by strong coupling between semiconductor exciton and microcavity photon.With effective mass 1...Nano Lett.,18,3335-3343(2018)Microcavity exciton-polariton is a Bosonic quasi-particle of half-matter and half-light formed by strong coupling between semiconductor exciton and microcavity photon.With effective mass 104times lower than electrons.展开更多
In this paper the bulk exciton polaritons in ternary mixed crystals （TMCs） are investigated in the Born-Huang approximation. The numerical results of the polariton frequencies as functions of the wave-vector and the...In this paper the bulk exciton polaritons in ternary mixed crystals （TMCs） are investigated in the Born-Huang approximation. The numerical results of the polariton frequencies as functions of the wave-vector and the compositions for ternary mixed crystals AlxGa1-xAs, CdxZn1-xSe, and AlxGa1-xN are obtained and discussed. The new dispersion characteristics for exciton-polaritons in TMC systems are found in comparison with binary crystals. The splitting of the two branches of exciton-polariton frequencies varies nonlinearly with the composition of TMCs and has a minimum in the long-wavelength range.展开更多
Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the nanoscale.One of the main obstacles for the development of single-particle nanolasers with all three dime...Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the nanoscale.One of the main obstacles for the development of single-particle nanolasers with all three dimensions shorter than the emitting wavelength in the visible range is the high lasing thresholds and the resulting overheating.Here we ex-ploit exciton-polariton condensation and mirror-image Mie modes in a cuboid CsPbBr3 nanoparticle to achieve coherent emission at the visible wavelength of around 0.53μm from its ultra-small(≈0.007μm3 or≈λ3/20)semiconductor nanocav-ity.The polaritonic nature of the emission from the nanocavity localized in all three dimensions is proven by direct com-parison with corresponding one-dimensional and two-dimensional waveguiding systems with similar material parameters.Such a deeply subwavelength nanolaser is enabled not only by the high values for exciton binding energy(≈35 meV),re-fractive index(>2.5 at low temperature),and luminescence quantum yield of CsPbBr3,but also by the optimization of po-laritons condensation on the Mie resonances with quality factors improved by the metallic substrate.Moreover,the key parameters for optimal lasing conditions are intermode free spectral range and phonons spectrum in CsPbBr3,which govern polaritons condensation path.Such chemically synthesized colloidal CsPbBr3 nanolasers can be potentially de-posited on arbitrary surfaces,which makes them a versatile tool for integration with various on-chip systems.展开更多
Exciton-polaritons offer an exceptional platform for future photoelectronic and quantum information applications. The influence of the optical Stark effect on exciton-polaritons in a microcavity embodied with a monola...Exciton-polaritons offer an exceptional platform for future photoelectronic and quantum information applications. The influence of the optical Stark effect on exciton-polaritons in a microcavity embodied with a monolayer WS2 is studied. A polarization dependent model is proposed to study the change of strongly coupled excitons and photons in a WS2 microcavity. It is revealed through both steady and dynamical states analysis that an outside optical Stark pulse can effectively vary the polariton characteristics, such as dispersion, exciton, and photon fractions, through blue shifting of excitonic resonance. Thus, the analysis and control of exciton-polaritons in a WS2 microcavity via a spin-selective trigger could be achievable.展开更多
Moirématerials,composed of two single-layer two-dimensional semiconductors,are important because they are good platforms for studying strongly correlated physics.Among them,moirématerials based on transition...Moirématerials,composed of two single-layer two-dimensional semiconductors,are important because they are good platforms for studying strongly correlated physics.Among them,moirématerials based on transition metal dichalcogenides(TMDs)have been intensively studied.The hetero-bilayer can support moiréinterlayer excitons if there is a small twist angle or small lattice constant difference between the TMDs in the hetero-bilayer and form a type-Ⅱ band alignment.The coupling of moiréinterlayer excitons to cavity modes can induce exotic phenomena.Here,we review recent advances in the coupling of moiréinterlayer excitons to cavities,and comment on the current difficulties and possible future research directions in this field.展开更多
The scope of the study is the spectra of low-temperature (T = 2K) photoluminescence of a p-CdTe/n-CdS film heterostructure comprising a monolayer of CdTe microcrystals, where a single microcrystalline particle is typi...The scope of the study is the spectra of low-temperature (T = 2K) photoluminescence of a p-CdTe/n-CdS film heterostructure comprising a monolayer of CdTe microcrystals, where a single microcrystalline particle is typically one micron in size. Focus is made on the dominant band of “super-hot” emission appearing in the spectral region located in energy above the fundamental absorption edge of a CdTe bulk crystal. A theoretical model has been developed that assumes the existence of a space-charge layer inside a microcrystal, which leads to the formation of a triangular potential well for an electron near the surface. The anomalous emission band arises as a result of the optical transitions of electrons from near-surface levels of spatial quantization to valence band states.展开更多
In this paper,we report the exciton polaritons in both positive and negative detuning micro cavities based on InGaN multi-quantum wells(MQWs)and the first polariton lasing in InGaN/GaN MQWs at room temperature by util...In this paper,we report the exciton polaritons in both positive and negative detuning micro cavities based on InGaN multi-quantum wells(MQWs)and the first polariton lasing in InGaN/GaN MQWs at room temperature by utilizing a 4.5λFabry-Perot(F-P)cavity with double dielectric distributed Bragg reflectors(DBRs).Double thresholds corresponding respectively to polariton lasing and photonic lasing are observed along with half-width narrowing and peak blue-shifts.The threshold of polariton lasing is about half of the threshold of photonic lasing.Our results paved a substantial way for ultra-low threshold lasers and room temperature Bose-Einstein Condensate(BEC)in nitride semiconductors.展开更多
The quantum features of the temporal photon statistics of an exciton-cavity coupled system in a quantum-well semiconductor microcavity are investigated analytically. Under the secular approximation, if the nonlinear i...The quantum features of the temporal photon statistics of an exciton-cavity coupled system in a quantum-well semiconductor microcavity are investigated analytically. Under the secular approximation, if the nonlinear interactions, i.e. the exciton-exciton coupling and the phase-space filling, are much weaker than the exciton-photon interaction, the evolution of the Fano factor shows that the distribution of the photon numbers exhibits the feature of collapses-revivals （CRs）, and the relevant revival time may be adjusted by several factors such as the total particle number, the detuning, and the nonlinear coupling strengths, etc. Especially, the ideal maximum antibunching with the minimum value 0 of the Fano factor occurs periodically for such a situation, with the dissipation of exciton-polariton being ignored.展开更多
In recent years,one-dimensional(1D)nanomaterials have raised researcher's interest because of their unique structur-al characteristic to generate and confine the optical signal and their promising prospects in pho...In recent years,one-dimensional(1D)nanomaterials have raised researcher's interest because of their unique structur-al characteristic to generate and confine the optical signal and their promising prospects in photonic applications.In this re-view,we summarized the recent research advances on the spectroscopy and carrier dynamics of 1D nanostructures.First,the condensation and propagation of exciton-polaritons in nanowires(NWs)are introduced.Second,we discussed the properties of 1D photonic crystal(PC)and applications in photonic-plasmonic structures.Third,the observation of topological edge states in 1D topological structures is introduced.Finally,the perspective on the potential opportunities and remaining chal-lenges of 1D nanomaterials is proposed.展开更多
In 1951,Huang firstly proposed the concept of polariton and derived its dispersion relation by combing lattice vibration in ionic crystals with electromagnetic waves using classic electromagnetic theory,which was prim...In 1951,Huang firstly proposed the concept of polariton and derived its dispersion relation by combing lattice vibration in ionic crystals with electromagnetic waves using classic electromagnetic theory,which was primarily aimed to explain light retardation effect (see Fig.1)[1].展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974071 and 62375040)the Sichuan Science and Technology Program(Grant Nos.2022ZYD0108 and 2023JDRC0030).
文摘This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analyses,strong coupling between excitons of perovskite and cavity photons is revealed,indicating the formation of polaritons in the perovskite microcavity.Besides,it is found that an external optical Stark pulse can induce energy shifts of excitons proportional to the pulse intensity,which modifies the dispersion characteristics of the polaritons.
文摘The low-temperature (T = 2 K) exciton-polariton luminescence (EPL) spectra in the vicinity of the exciton-resonance frequency An=1 for CdS-type crystals have been theoretically and experimentally investigated with allowance for the mechanical exciton decay . The results of the numerical calculations of the partial and interference contributions of the bulk and radiative surface spectral modes to the EPL in the geometry of additional s- and p-polarized waves emitted into vacuum are analyzed. It is shown that the contributions of purely longitudinal excitons and their interference with polaritons of the upper dispersion branch near the longitudinal frequency ωL to the EPL are small (∼10% - 30%);nevertheless, they must be taken into account to obtain quantitative agreement with experimental data. Specifically these contributions are responsible for the formation of an additional line (along with the fundamental AT line) in the case of oblique incidence of radiation.
文摘Nano Lett.,18,3335-3343(2018)Microcavity exciton-polariton is a Bosonic quasi-particle of half-matter and half-light formed by strong coupling between semiconductor exciton and microcavity photon.With effective mass 104times lower than electrons.
基金Project supported partly by PhD Progress Foundation of Higher Education Institutions of China （Grant No 20040126003） and the Natural Science Foundation of Inner Mongol of China （Grant No 200408020101）.
文摘In this paper the bulk exciton polaritons in ternary mixed crystals （TMCs） are investigated in the Born-Huang approximation. The numerical results of the polariton frequencies as functions of the wave-vector and the compositions for ternary mixed crystals AlxGa1-xAs, CdxZn1-xSe, and AlxGa1-xN are obtained and discussed. The new dispersion characteristics for exciton-polaritons in TMC systems are found in comparison with binary crystals. The splitting of the two branches of exciton-polariton frequencies varies nonlinearly with the composition of TMCs and has a minimum in the long-wavelength range.
基金supported by the Federal Program'Priority 2030'and NSFC(Project 62350610272)A.K.Samusev acknowledges Deutsche Forschungsgemeinschaft-project No.529710370。
文摘Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the nanoscale.One of the main obstacles for the development of single-particle nanolasers with all three dimensions shorter than the emitting wavelength in the visible range is the high lasing thresholds and the resulting overheating.Here we ex-ploit exciton-polariton condensation and mirror-image Mie modes in a cuboid CsPbBr3 nanoparticle to achieve coherent emission at the visible wavelength of around 0.53μm from its ultra-small(≈0.007μm3 or≈λ3/20)semiconductor nanocav-ity.The polaritonic nature of the emission from the nanocavity localized in all three dimensions is proven by direct com-parison with corresponding one-dimensional and two-dimensional waveguiding systems with similar material parameters.Such a deeply subwavelength nanolaser is enabled not only by the high values for exciton binding energy(≈35 meV),re-fractive index(>2.5 at low temperature),and luminescence quantum yield of CsPbBr3,but also by the optimization of po-laritons condensation on the Mie resonances with quality factors improved by the metallic substrate.Moreover,the key parameters for optimal lasing conditions are intermode free spectral range and phonons spectrum in CsPbBr3,which govern polaritons condensation path.Such chemically synthesized colloidal CsPbBr3 nanolasers can be potentially de-posited on arbitrary surfaces,which makes them a versatile tool for integration with various on-chip systems.
基金supported by the National Natural Sci-ence Foundation of China(No.21972083,No.22102129)the Fundamental Research Funds for the Central Universities(GK202102008)+1 种基金the Support Program for top-notch young talents in Shaanxi Province(1511000066)the China Postdoctoral Science Foundation(2021M692615,2022T150528)。
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61811530062and 61575040)the Sichuan Science and Technology Program(No.2018HH0148)
文摘Exciton-polaritons offer an exceptional platform for future photoelectronic and quantum information applications. The influence of the optical Stark effect on exciton-polaritons in a microcavity embodied with a monolayer WS2 is studied. A polarization dependent model is proposed to study the change of strongly coupled excitons and photons in a WS2 microcavity. It is revealed through both steady and dynamical states analysis that an outside optical Stark pulse can effectively vary the polariton characteristics, such as dispersion, exciton, and photon fractions, through blue shifting of excitonic resonance. Thus, the analysis and control of exciton-polaritons in a WS2 microcavity via a spin-selective trigger could be achievable.
基金supported by the National Key R&D Program of China(Grant No.2018YFA036900)the Beijing Natural Science Foundation(Grant No.JQ21018)。
文摘Moirématerials,composed of two single-layer two-dimensional semiconductors,are important because they are good platforms for studying strongly correlated physics.Among them,moirématerials based on transition metal dichalcogenides(TMDs)have been intensively studied.The hetero-bilayer can support moiréinterlayer excitons if there is a small twist angle or small lattice constant difference between the TMDs in the hetero-bilayer and form a type-Ⅱ band alignment.The coupling of moiréinterlayer excitons to cavity modes can induce exotic phenomena.Here,we review recent advances in the coupling of moiréinterlayer excitons to cavities,and comment on the current difficulties and possible future research directions in this field.
文摘The scope of the study is the spectra of low-temperature (T = 2K) photoluminescence of a p-CdTe/n-CdS film heterostructure comprising a monolayer of CdTe microcrystals, where a single microcrystalline particle is typically one micron in size. Focus is made on the dominant band of “super-hot” emission appearing in the spectral region located in energy above the fundamental absorption edge of a CdTe bulk crystal. A theoretical model has been developed that assumes the existence of a space-charge layer inside a microcrystal, which leads to the formation of a triangular potential well for an electron near the surface. The anomalous emission band arises as a result of the optical transitions of electrons from near-surface levels of spatial quantization to valence band states.
基金National Key Research and Development Program of China(No.2016YFB0400803)the Science Challenge Project(No.TZ2016003)the National Natural Science Foundation of China(Nos.61704140,U1505253).
文摘In this paper,we report the exciton polaritons in both positive and negative detuning micro cavities based on InGaN multi-quantum wells(MQWs)and the first polariton lasing in InGaN/GaN MQWs at room temperature by utilizing a 4.5λFabry-Perot(F-P)cavity with double dielectric distributed Bragg reflectors(DBRs).Double thresholds corresponding respectively to polariton lasing and photonic lasing are observed along with half-width narrowing and peak blue-shifts.The threshold of polariton lasing is about half of the threshold of photonic lasing.Our results paved a substantial way for ultra-low threshold lasers and room temperature Bose-Einstein Condensate(BEC)in nitride semiconductors.
文摘The quantum features of the temporal photon statistics of an exciton-cavity coupled system in a quantum-well semiconductor microcavity are investigated analytically. Under the secular approximation, if the nonlinear interactions, i.e. the exciton-exciton coupling and the phase-space filling, are much weaker than the exciton-photon interaction, the evolution of the Fano factor shows that the distribution of the photon numbers exhibits the feature of collapses-revivals （CRs）, and the relevant revival time may be adjusted by several factors such as the total particle number, the detuning, and the nonlinear coupling strengths, etc. Especially, the ideal maximum antibunching with the minimum value 0 of the Fano factor occurs periodically for such a situation, with the dissipation of exciton-polariton being ignored.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB36000000)National Natural Science Foundation of China(22073022,11874130,12074086,22173025)+3 种基金the Support by the DNL Cooperation Fund,CAS(DNL202016)China Postdoctoral Science Foundation(2022M710925)Beijing Municipal Natural Science Foundation(1222030)the CAS Instrument Development Project(No.Y950291).
文摘In recent years,one-dimensional(1D)nanomaterials have raised researcher's interest because of their unique structur-al characteristic to generate and confine the optical signal and their promising prospects in photonic applications.In this re-view,we summarized the recent research advances on the spectroscopy and carrier dynamics of 1D nanostructures.First,the condensation and propagation of exciton-polaritons in nanowires(NWs)are introduced.Second,we discussed the properties of 1D photonic crystal(PC)and applications in photonic-plasmonic structures.Third,the observation of topological edge states in 1D topological structures is introduced.Finally,the perspective on the potential opportunities and remaining chal-lenges of 1D nanomaterials is proposed.
文摘In 1951,Huang firstly proposed the concept of polariton and derived its dispersion relation by combing lattice vibration in ionic crystals with electromagnetic waves using classic electromagnetic theory,which was primarily aimed to explain light retardation effect (see Fig.1)[1].
