We propose and demonstrate a cryogenic thermo-optic(TO)modulator in x-cut thin-film lithium niobate(TFLN)with an NbN superconducting heater.Compared to a conventional metal heating electrode,a fast and energy-efficien...We propose and demonstrate a cryogenic thermo-optic(TO)modulator in x-cut thin-film lithium niobate(TFLN)with an NbN superconducting heater.Compared to a conventional metal heating electrode,a fast and energy-efficient modulation is obtained by placing an NbN superconducting heating electrode above the TFLN waveguide.The transition of the NbN superconducting electrode between superconducting and normal states turns the heating and cooling processes from continuous to discontinuous change.Thus,the energy consumption during the modulation process is reduced proportionally.The rise/fall time of the proposed device is 22μs/15μs,which has been the fastest response time reported in TFLN thermo-optic modulators so far.The presented TO modulator can easily be used at cryogenic temperatures and has great potential for applications in cryogenic optoelectronics.展开更多
基金supported by the Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX03)the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(No.XDA18040300).
文摘We propose and demonstrate a cryogenic thermo-optic(TO)modulator in x-cut thin-film lithium niobate(TFLN)with an NbN superconducting heater.Compared to a conventional metal heating electrode,a fast and energy-efficient modulation is obtained by placing an NbN superconducting heating electrode above the TFLN waveguide.The transition of the NbN superconducting electrode between superconducting and normal states turns the heating and cooling processes from continuous to discontinuous change.Thus,the energy consumption during the modulation process is reduced proportionally.The rise/fall time of the proposed device is 22μs/15μs,which has been the fastest response time reported in TFLN thermo-optic modulators so far.The presented TO modulator can easily be used at cryogenic temperatures and has great potential for applications in cryogenic optoelectronics.