We have proposed and experimentally demonstrated a novel scheme for efficient mid-infrared difference-frequency generation based on passively synchronized fiber lasers. The adoption of coincident seeding pulses in the...We have proposed and experimentally demonstrated a novel scheme for efficient mid-infrared difference-frequency generation based on passively synchronized fiber lasers. The adoption of coincident seeding pulses in the nonlinear conversion process could substantially lower the pumping threshold for mid-infrared parametric emission. Consequently,a picosecond mid-infrared source at 3.1 μm was prepared with watt-level average power, and a maximum power conversion efficiency of 77% was realized from pump to down-converted light. Additionally, the long-term stability of generated power was manifested with a relative fluctuation as low as 0.17% over one hour. Thanks to the all-optical passive synchronization and all-polarization-maintaining fiber architecture, the implemented laser system was also featured with simplicity, compactness and robustness, which would favor subsequent applications beyond laboratory operation.展开更多
Optical detectors with single-photon sensitivity and large dynamic range would facilitate a variety of applications.Specifically,the capability of extending operation wavelengths into the mid-infrared region is highly...Optical detectors with single-photon sensitivity and large dynamic range would facilitate a variety of applications.Specifically,the capability of extending operation wavelengths into the mid-infrared region is highly attractive.Here we implement a mid-infrared frequency upconversion detector for counting and resolving photons at 3μm.Thanks to the spectrotemporal engineering of the involved optical fields,the mid-infrared photons could be spectrally translated into the visible band with a conversion efficiency of 80%.In combination with a silicon avalanche photodiode,we obtained unprecedented performance with a high overall detection efficiency of 37%and a low noise equivalent power of 1.8×10^(-17) W∕Hz1∕2.Furthermore,photon-number-resolving detection at mid-infrared wavelengths was demonstrated,for the first time to our knowledge,with a multipixel photon counter.The implemented upconversion detector exhibited a maximal resolving photon number up to 9 with a noise probability per pulse of 0.14%at the peak detection efficiency.The achieved photon counting and resolving performance might open up new possibilities in trace molecule spectroscopy,sensitive biochemical sensing,and free-space communications,among others.展开更多
In this paper, we demonstrated a series of short-living mode-locking(ML) states(each lasting a few to a hundred microseconds) that happened before a fiber laser reached a steady ML state.With time-stretched dispersion...In this paper, we demonstrated a series of short-living mode-locking(ML) states(each lasting a few to a hundred microseconds) that happened before a fiber laser reached a steady ML state.With time-stretched dispersion Fourier transform spectroscopy, a rich diversity of transient multi-pulse dynamics were revealed spectrally and temporally.As a result, we found that the formation of the short-living ML states was related to abundant pump power, and their decaying evolution dynamics were possibly governed by gain depletion and recovery.Our results revealed unexpected transient lasing behaviors of a soliton laser and thus might be useful to understand the complex dynamics of mode-locked lasers.展开更多
基金supported in part by the National Key Research and Development Program(No.2018YFB0407100)Science and Technology Innovation Program of Basic Science Foundation of Shanghai(No.18JC1412000)+1 种基金Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning,National Natural Science Foundation of China(Nos.11621404 and 11727812)Shanghai Municipal Science and Technology Major Project(No.2019SHZDZX01)。
文摘We have proposed and experimentally demonstrated a novel scheme for efficient mid-infrared difference-frequency generation based on passively synchronized fiber lasers. The adoption of coincident seeding pulses in the nonlinear conversion process could substantially lower the pumping threshold for mid-infrared parametric emission. Consequently,a picosecond mid-infrared source at 3.1 μm was prepared with watt-level average power, and a maximum power conversion efficiency of 77% was realized from pump to down-converted light. Additionally, the long-term stability of generated power was manifested with a relative fluctuation as low as 0.17% over one hour. Thanks to the all-optical passive synchronization and all-polarization-maintaining fiber architecture, the implemented laser system was also featured with simplicity, compactness and robustness, which would favor subsequent applications beyond laboratory operation.
基金National Key Research and Development Program of China(2018YFB0407100)Science and Technology Innovation Program of Basic Science Foundation of Shanghai(18JC1412000)+2 种基金Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher LearningNational Natural Science Foundation of China(11621404,11727812)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)。
文摘Optical detectors with single-photon sensitivity and large dynamic range would facilitate a variety of applications.Specifically,the capability of extending operation wavelengths into the mid-infrared region is highly attractive.Here we implement a mid-infrared frequency upconversion detector for counting and resolving photons at 3μm.Thanks to the spectrotemporal engineering of the involved optical fields,the mid-infrared photons could be spectrally translated into the visible band with a conversion efficiency of 80%.In combination with a silicon avalanche photodiode,we obtained unprecedented performance with a high overall detection efficiency of 37%and a low noise equivalent power of 1.8×10^(-17) W∕Hz1∕2.Furthermore,photon-number-resolving detection at mid-infrared wavelengths was demonstrated,for the first time to our knowledge,with a multipixel photon counter.The implemented upconversion detector exhibited a maximal resolving photon number up to 9 with a noise probability per pulse of 0.14%at the peak detection efficiency.The achieved photon counting and resolving performance might open up new possibilities in trace molecule spectroscopy,sensitive biochemical sensing,and free-space communications,among others.
基金supported by the National Key Research and Development Program (No.2018YFB0504400)National Natural Science Foundation of China (NSFC)(Nos.61875243and 11804100)+1 种基金Shanghai Municipal Science and Technology Major Project (No.2019SHZDZX01)Science and Technology Innovation Program of Basic Science Foundation of Shanghai (No.18JC1412000)。
文摘In this paper, we demonstrated a series of short-living mode-locking(ML) states(each lasting a few to a hundred microseconds) that happened before a fiber laser reached a steady ML state.With time-stretched dispersion Fourier transform spectroscopy, a rich diversity of transient multi-pulse dynamics were revealed spectrally and temporally.As a result, we found that the formation of the short-living ML states was related to abundant pump power, and their decaying evolution dynamics were possibly governed by gain depletion and recovery.Our results revealed unexpected transient lasing behaviors of a soliton laser and thus might be useful to understand the complex dynamics of mode-locked lasers.
