Terahertz （THz） random lazing is studied numerically for two-dimensional disordered media made of ruby grains with a three-level atomic system. A method via the adjustment of the pumping area to control the polariza...Terahertz （THz） random lazing is studied numerically for two-dimensional disordered media made of ruby grains with a three-level atomic system. A method via the adjustment of the pumping area to control the polarization of the THz wave is proposed. Computed results reveal that transverse electric THz lasing modes could occur if pumping is supplied on the whole medium, while transverse magnetic THz lasing modes could occur if pumping is appropriately supplied on a partial area of the medium.展开更多
Spatio-temporal imaging of light propagation is very important in photonics because it provides the most direct tool available to study the interaction between light and its host environment.Sub-ps time resolution is ...Spatio-temporal imaging of light propagation is very important in photonics because it provides the most direct tool available to study the interaction between light and its host environment.Sub-ps time resolution is needed to investigate the fine and complex structural features that characterize disordered and heterogeneous structures,which are responsible for a rich array of transport physics that have not yet been fully explored.A newly developed wide-field imaging system enables us to present a spatiotemporal study on light transport in various disordered media,revealing properties that could not be properly assessed using standard techniques.By extending our investigation to an almost transparent membrane,a configuration that has been difficult to characterize until now,we unveil the peculiar physics exhibited by such thin scattering systems with transport features that go beyond mainstream diffusion modeling,despite the occurrence of multiple scattering.展开更多
基金Project supported by the Fundamental Research Fund for the Central Universities of Ministry of Education of China (Grant No.2010MS041)the National Natural Science Foundation of China (Grant No.60778003)the Science Foundation of China Academy of Engineering Physics NSAF (Grant No.10876010)
文摘Terahertz （THz） random lazing is studied numerically for two-dimensional disordered media made of ruby grains with a three-level atomic system. A method via the adjustment of the pumping area to control the polarization of the THz wave is proposed. Computed results reveal that transverse electric THz lasing modes could occur if pumping is supplied on the whole medium, while transverse magnetic THz lasing modes could occur if pumping is appropriately supplied on a partial area of the medium.
基金supported by the European Network of Excellence Nanophotonics for Energy Efficiency and the ERC through the Advanced Grant PhotBots(Proj.Ref.291349).
文摘Spatio-temporal imaging of light propagation is very important in photonics because it provides the most direct tool available to study the interaction between light and its host environment.Sub-ps time resolution is needed to investigate the fine and complex structural features that characterize disordered and heterogeneous structures,which are responsible for a rich array of transport physics that have not yet been fully explored.A newly developed wide-field imaging system enables us to present a spatiotemporal study on light transport in various disordered media,revealing properties that could not be properly assessed using standard techniques.By extending our investigation to an almost transparent membrane,a configuration that has been difficult to characterize until now,we unveil the peculiar physics exhibited by such thin scattering systems with transport features that go beyond mainstream diffusion modeling,despite the occurrence of multiple scattering.
