A wideband tunable frequency-doubling optoelectronic oscillator （FD-OEO） is proposed and experimentally demonstrated based on a polarization modulator and an optical bandpass filter （OBPF）. The central frequency o...A wideband tunable frequency-doubling optoelectronic oscillator （FD-OEO） is proposed and experimentally demonstrated based on a polarization modulator and an optical bandpass filter （OBPF）. The central frequency of the correspondingly fundamental OEO could be adjusted by tuning the bandwidth and central frequency of the OBPF, which could also be regarded as a photonic-assisted tunable microwave filter. The frequency tuning range of the FD-OEO covers from 9.5 to 32.8？GHz, and the single sideband phase noise of the fundamental signal is lower than -100dBc/Hz at an offset of 10？kHz. Moreover, the frequency stability of the generated signal is investigated by measuring its Allan deviation. The Allan deviation of the generated fundamental signal at 10？GHz is 2.39×10^-9.展开更多
A transverse relaxation determination of spin-exchange relaxation free （SERF） magnetometer based on polarization modulation technique is proposed. Compared with the radio-frequency （RF） excitation and light intens...A transverse relaxation determination of spin-exchange relaxation free （SERF） magnetometer based on polarization modulation technique is proposed. Compared with the radio-frequency （RF） excitation and light intensity excitation meth- ods used in SERF magnetometer, the light polarization modulation method has a high stability in low-frequency range, which indicates a more accurate transverse relaxation measurement.展开更多
Optical metasurfaces allow complex light manipulation within subwavelength thicknesses and are thus rapidly emerging as a key enabling technology for nanophotonics applications.The control over light polarization alre...Optical metasurfaces allow complex light manipulation within subwavelength thicknesses and are thus rapidly emerging as a key enabling technology for nanophotonics applications.The control over light polarization already provided a route towards ultracompact metasurface-based polarimetry devices.If translated to the nonlinear optical regime it may become a transformative tool for nonlinear imaging,optical holography,and sensing.Here,we report ultrafast all-optical polarization modulation of upconverted light by all-dielectric metasurfaces via nonlinear interferometry.By controlling the relative phase between a pump beam atωand its frequency-doubled replica at 2ω,we can set the phase relation between two frequency-degenerate upconversion processes at 3ω–sum-frequency generation and third-harmonic generation–stemming from an AlGaAs metasurface.By leveraging the opposite parity of the two nonlinear processes and adjusting their relative intensities,we achieve a modulation of the polarization state of the upconverted light between linear and circular states with a circular polarization degree of up to 83%.Remarkably,circularly polarized light of opposite handedness is symmetrically mapped in the Fourier space,at coincidence with the first diffraction orders of the metasurface.Furthermore,the handedness can be completely reversed within the same diffraction order by applying a phase delay ofπ.Our work adds an additional modulation layer beyond intensity to all-optical routing with precise phase control:polarization.The capability to encode and modulate simultaneously different polarization states in the k-space holds potential for chiral sensing and advanced imaging techniques.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61675196the National Basic Research Program of China under Grant No 2014CB340102+1 种基金the National High-Tech Research and Development Program of China under Grant No 2015AA016903the Open Research of Beijing University of Posts and Telecommunications under Grant No IOOC2013A002
文摘A wideband tunable frequency-doubling optoelectronic oscillator （FD-OEO） is proposed and experimentally demonstrated based on a polarization modulator and an optical bandpass filter （OBPF）. The central frequency of the correspondingly fundamental OEO could be adjusted by tuning the bandwidth and central frequency of the OBPF, which could also be regarded as a photonic-assisted tunable microwave filter. The frequency tuning range of the FD-OEO covers from 9.5 to 32.8？GHz, and the single sideband phase noise of the fundamental signal is lower than -100dBc/Hz at an offset of 10？kHz. Moreover, the frequency stability of the generated signal is investigated by measuring its Allan deviation. The Allan deviation of the generated fundamental signal at 10？GHz is 2.39×10^-9.
基金Project supported by the National Natural Science Foundation of China(Grant No.61227902)the National Key R&D Program of China(Grant No.2017YFB0503100)the Natural Science Foundation of Beijing Municipality,China(Grant No.4162038)
文摘A transverse relaxation determination of spin-exchange relaxation free （SERF） magnetometer based on polarization modulation technique is proposed. Compared with the radio-frequency （RF） excitation and light intensity excitation meth- ods used in SERF magnetometer, the light polarization modulation method has a high stability in low-frequency range, which indicates a more accurate transverse relaxation measurement.
基金financial support from Project NQSTI—ID PE_00000023 funded by the European Union under the Next Generation EU program-CUP H43C22000870001 Spoke 6.A.Z.,M.F.and M.C.would like to thank C.De Angelis and D.Rocco for insightful discussions.
文摘Optical metasurfaces allow complex light manipulation within subwavelength thicknesses and are thus rapidly emerging as a key enabling technology for nanophotonics applications.The control over light polarization already provided a route towards ultracompact metasurface-based polarimetry devices.If translated to the nonlinear optical regime it may become a transformative tool for nonlinear imaging,optical holography,and sensing.Here,we report ultrafast all-optical polarization modulation of upconverted light by all-dielectric metasurfaces via nonlinear interferometry.By controlling the relative phase between a pump beam atωand its frequency-doubled replica at 2ω,we can set the phase relation between two frequency-degenerate upconversion processes at 3ω–sum-frequency generation and third-harmonic generation–stemming from an AlGaAs metasurface.By leveraging the opposite parity of the two nonlinear processes and adjusting their relative intensities,we achieve a modulation of the polarization state of the upconverted light between linear and circular states with a circular polarization degree of up to 83%.Remarkably,circularly polarized light of opposite handedness is symmetrically mapped in the Fourier space,at coincidence with the first diffraction orders of the metasurface.Furthermore,the handedness can be completely reversed within the same diffraction order by applying a phase delay ofπ.Our work adds an additional modulation layer beyond intensity to all-optical routing with precise phase control:polarization.The capability to encode and modulate simultaneously different polarization states in the k-space holds potential for chiral sensing and advanced imaging techniques.
