The importance of tunable subwavelength optical devices in modern electromagnetic and photonic systems is indisputable.Herein,a lithography-free,wide-angle,and reconfigurable subwavelength optical device with high tun...The importance of tunable subwavelength optical devices in modern electromagnetic and photonic systems is indisputable.Herein,a lithography-free,wide-angle,and reconfigurable subwavelength optical device with high tunability operating in the near-infrared regions is proposed and experimentally demonstrated,based on a reversible nanochemistry approach.The reconfigurable subwavelength optical device basically comprises an ultrathin copper oxide(CuO)thin film on an optical thick gold substrate by utilizing the reversible chemical conversion of CuO to sulfides upon exposure to hydrogen sulfide gas.Proof-of-concept experimental results show that the maximal modulation depth of reflectance can be as high as 90%at the wavelength of 1.79μm with the initial thickness of CuO taken as 150 nm.Partially reflected wave calculations combined with the transfer matrix method are employed to analytically investigate the optical properties of the structure,which show good agreement with experimental results.We believe that the proposed versatile approaches can be implemented for dynamic control management,allowing applications in tunable photonics,active displays,optical encryption,and gas sensing.展开更多
Fabry-Perot(F-P)nanocavity-type electrochromic devices with multicolor tunability have attracted significant interest in the past two years for their potential uses in a wide variety of applications,such as electronic...Fabry-Perot(F-P)nanocavity-type electrochromic devices with multicolor tunability have attracted significant interest in the past two years for their potential uses in a wide variety of applications,such as electronic display,military camouflage,and dynamic decoration.However,challenges such as insufficient brightness,lengthy switching times,and poor cycling stability have yet to be overcome.Herein,we demonstrate electrochromic electrodes based on ITO/Cu as both the current collector and the reflective layer,with WO_(3 )as the electrochromic material,forming a unique three-layered structure.The constituted WO_(3 )/ITO/Cu films present a high brightness value of about 84%before coloration,and a decent brightness value of 48%after coloration at−0.8V.Moreover,a fast switching time between different coloration states(tc=2.2s;tb=1s)is recorded,attributed to the extremely low sheet resistivity of the ITO/Cu current collector.The films also reveal excellent electrochemical cycling stability across 2000 cycles.展开更多
基金National Key Research and Development Program of China(2017YFA0205800)National Natural Science Foundation of China(61471345,62075231)+3 种基金Science and Technology Commission of Shanghai Municipality(20JC1414603)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)Shanghai Innovation Project(2021-cyxt1-kj04)Fundamental Research Funds for the Central Universities.
文摘The importance of tunable subwavelength optical devices in modern electromagnetic and photonic systems is indisputable.Herein,a lithography-free,wide-angle,and reconfigurable subwavelength optical device with high tunability operating in the near-infrared regions is proposed and experimentally demonstrated,based on a reversible nanochemistry approach.The reconfigurable subwavelength optical device basically comprises an ultrathin copper oxide(CuO)thin film on an optical thick gold substrate by utilizing the reversible chemical conversion of CuO to sulfides upon exposure to hydrogen sulfide gas.Proof-of-concept experimental results show that the maximal modulation depth of reflectance can be as high as 90%at the wavelength of 1.79μm with the initial thickness of CuO taken as 150 nm.Partially reflected wave calculations combined with the transfer matrix method are employed to analytically investigate the optical properties of the structure,which show good agreement with experimental results.We believe that the proposed versatile approaches can be implemented for dynamic control management,allowing applications in tunable photonics,active displays,optical encryption,and gas sensing.
基金National Key Research and Development Program of China(2020YFB1505703)This work is supported by the National Natural Science Foundation of China(52172299,22175198,51972331)+2 种基金Z.G.Z would like to acknowledge the support from the External Cooperation Program of the Chinese Academy of Sciences(121E32KYSB20190008)Six Talent Peaks Project of Jiangsu Province(XCL-170).S.C would like to acknowledge the support from the Youth Innovation Promotion Association,CAS(2018356)Outstanding Youth Fund of Jiangxi(20192BCBL23027).
文摘Fabry-Perot(F-P)nanocavity-type electrochromic devices with multicolor tunability have attracted significant interest in the past two years for their potential uses in a wide variety of applications,such as electronic display,military camouflage,and dynamic decoration.However,challenges such as insufficient brightness,lengthy switching times,and poor cycling stability have yet to be overcome.Herein,we demonstrate electrochromic electrodes based on ITO/Cu as both the current collector and the reflective layer,with WO_(3 )as the electrochromic material,forming a unique three-layered structure.The constituted WO_(3 )/ITO/Cu films present a high brightness value of about 84%before coloration,and a decent brightness value of 48%after coloration at−0.8V.Moreover,a fast switching time between different coloration states(tc=2.2s;tb=1s)is recorded,attributed to the extremely low sheet resistivity of the ITO/Cu current collector.The films also reveal excellent electrochemical cycling stability across 2000 cycles.
