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
Mars is the terrestrial planet in the solar system that is closest to the Earth.Studying the atmospheric parameters of Mars and studying the evolutionary history of the Martian environment on this basis is helpful for...Mars is the terrestrial planet in the solar system that is closest to the Earth.Studying the atmospheric parameters of Mars and studying the evolutionary history of the Martian environment on this basis is helpful for people to discover signs of extraterrestrial life and to study the trend of climate change on Earth.Mie–Rayleigh scattering lidar is an important technology for detecting parameters from the surface to the middle and upper atmosphere.Because of the different aerosol distributions,Mie scattering and Rayleigh scattering have their own optimal detection ranges.Given the long period and high cost of any deep space exploration program,it is important to conduct sufficient feasibility studies and parameter simulations before the payload is launched.In this study,a parameterized lidar mathematical model and Earth’s atmospheric mode are used to compare with the measured signals of ground-based Mie–Rayleigh scattering lidar,and the correctness of the lidar mathematical model is verified.Using the model,we select the landing area of Tianwen-1 and substitute it into the Martian atmospheric mode,and then the Mie–Rayleigh lidar backscattering signal and the key parameters of the lidar system are systematically analyzed under the conditions of a clean Martian atmosphere and a global sandstorm.In addition,the optimal detection altitude ranges of Mie scattering and Rayleigh scattering on Mars under different atmospheric conditions are obtained,which provides a reference for the practical design and development of the subsequent lidar system for the Martian atmospheric environment.展开更多
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financial support from the B-type Strategic Priority Program of the Chinese Academy of Sciences (Grant No. XDB41030000)the National Natural Science Foundation of China (Grant Nos. 42125402, 42188101, 42304165, and 42374182)+2 种基金the Key-Area Research and Development Program of Guangdong Province (Grant No. 2020B0303020001)the Shanghai Municipal Science and Technology Major Project (Grant No. 2019SHZDZX01)the Innovation Program for Quantum Science and Technology (Grant No. 2021ZD0300302)
文摘Mars is the terrestrial planet in the solar system that is closest to the Earth.Studying the atmospheric parameters of Mars and studying the evolutionary history of the Martian environment on this basis is helpful for people to discover signs of extraterrestrial life and to study the trend of climate change on Earth.Mie–Rayleigh scattering lidar is an important technology for detecting parameters from the surface to the middle and upper atmosphere.Because of the different aerosol distributions,Mie scattering and Rayleigh scattering have their own optimal detection ranges.Given the long period and high cost of any deep space exploration program,it is important to conduct sufficient feasibility studies and parameter simulations before the payload is launched.In this study,a parameterized lidar mathematical model and Earth’s atmospheric mode are used to compare with the measured signals of ground-based Mie–Rayleigh scattering lidar,and the correctness of the lidar mathematical model is verified.Using the model,we select the landing area of Tianwen-1 and substitute it into the Martian atmospheric mode,and then the Mie–Rayleigh lidar backscattering signal and the key parameters of the lidar system are systematically analyzed under the conditions of a clean Martian atmosphere and a global sandstorm.In addition,the optimal detection altitude ranges of Mie scattering and Rayleigh scattering on Mars under different atmospheric conditions are obtained,which provides a reference for the practical design and development of the subsequent lidar system for the Martian atmospheric environment.
