Bessel beam featured with self-healing is essential to the optical sensing applications in the obstacle scattering environment.Integrated on-chip generation of the Bessel beam outperforms the conventional structure by...Bessel beam featured with self-healing is essential to the optical sensing applications in the obstacle scattering environment.Integrated on-chip generation of the Bessel beam outperforms the conventional structure by small size,robustness,and alignment-free scheme.However,the maximum propagation distance(Z_(max))provided by the existing approaches cannot support long-range sensing,and thus,it restricts its potential applications.In this work,we propose an integrated silicon photonic chip with unique structures featured with concentrically distributed grating arrays to generate the Bessel-Gaussian beam with a long propagation distance.The spot with the Bessel function profile is measured at 10.24m without optical lenses,and the photonic chip’s operation wavelength can be continuously performed from 1500 to 1630 nm.To demonstrate the functionality of the generated Bessel-Gaussian beam,we also experimentally measure the rotation speeds of a spinning object via the rotational Doppler Effect and the distance through the phase laser ranging principle.The maximum error of the rotation speed in this experiment is measured to be 0.05%,indicating the minimum error in the current reports.By the compact size,low cost,and mass production potential of the integrated process,our approach is promising to readily enable the Bessel-Gaussian beam in widespread optical communication and micro-manipulation applications.展开更多
Optical phased array(OPA)technology is considered a promising solution for solid-state beam steering to supersede the traditional mechanical beam steering.As a key component of the LIDAR system for long-range detectio...Optical phased array(OPA)technology is considered a promising solution for solid-state beam steering to supersede the traditional mechanical beam steering.As a key component of the LIDAR system for long-range detection,OPAs featuring a wide steering angle and high resolution without beam aliasing are highly desired.However,a wide steering range requires a waveguide pitch less than half of the wavelength,which is easily subjected to cross talk.Besides,high resolution requires a large aperture,and it is normally achieved by a high count number of waveguides,which complicates the control system.To solve the mentioned issues,we design two high-performance 128-channel OPAs fabricated on a multilayered SiN-on-SOI platform.Attributed to the nonuniform antenna pitch,only 128 waveguides are used to achieve a 4 mm wide aperture.Besides,by virtue of innovative dual-level silicon nitride(Si_(3)N_(4))waveguide grating antennas,the fishbone antenna OPA achieves a 100°×19.4°field of view(FOV)with divergence of 0.021°×0.029°,and the chain antenna OPA realizes a 140°×19.23°FOV with divergence of 0.021°×0.1°.To our best knowledge,140°is the widest lateral steering range in two-dimensional OPA,and 0.029°is the smallest longitudinal divergence.Finally,we embed the OPA into a frequency-modulated continuous-wave system to achieve 100 m distance measurement.The reflected signal from 100 m distance is well detected with 26 dBm input transmitter power,which proves that OPA serves as a promising candidate for transceiving optical signal in a LIDAR system.展开更多
To optimize the dark current characteristic and detection efficiency of the 1550 nm weak light signal at room temperature,this work proposes a Ge-on-Si avalanche photodiode[APD]in Geiger mode,which could operate at 30...To optimize the dark current characteristic and detection efficiency of the 1550 nm weak light signal at room temperature,this work proposes a Ge-on-Si avalanche photodiode[APD]in Geiger mode,which could operate at 300 K.This lateral separate absorption charge multiplication APD shows a low breakdown voltage[V_(br)]in Geiger mode of-7.42 V and low dark current of 0.096 n A at unity gain voltage[V_(Gain)=1=-7.03 V].Combined with an RF amplifier module and counter,the detection system demonstrates a low dark count rate[DCR]of 1.1×10^(6) counts per second and high detection efficiencyηof 7.8%for 1550 nm weak coherent pulse detection at 300 K.The APD reported in this work weakens the dependence of the weak optical signal recognition on the low environment temperature and makes single-chip integration of the single-photon level detection system possible.展开更多
Germanium-on-silicon(Ge-on-Si) avalanche photodiodes(APDs) are widely used in near-infrared detection, laser ranging, free space communication, quantum communication, and other fields. However, the existence of lattic...Germanium-on-silicon(Ge-on-Si) avalanche photodiodes(APDs) are widely used in near-infrared detection, laser ranging, free space communication, quantum communication, and other fields. However, the existence of lattice defects at the Ge/Si interface causes a high dark current in the Ge-on-Si APD, degrading the device sensitivity and also increasing energy consumption in integrated circuits. In this work, we propose a novel surface illuminated Ge-on-Si APD architecture with three terminals. Besides two electrodes on Si substrates, a third electrode is designed for Ge to regulate the control current and bandwidth, achieving multiple outputs of a single device and reducing the dark current of the device. When the voltage on Ge is -27.5 V, the proposed device achieves a dark current of 100 n A, responsivity of 9.97 A/W at -40 d Bm input laser power at 1550 nm, and optimal bandwidth of 142 MHz. The low dark current and improved responsivity can meet the requirements of autonomous driving and other applications demanding weak light detection.展开更多
基金supported by National Key R&D Program of China under Grants no.2022YFB2804504The National Natural Science Foundation of China under Grants nos.62090054,61934003,62105173 and 62105174+1 种基金Major scientific and technological program of Jilin Province under Grants nos.20200501007GX and 20210301014GXProgram for JLU Science and Technology Innovative Research Team(JLUSTIRT,2021TD-39).
文摘Bessel beam featured with self-healing is essential to the optical sensing applications in the obstacle scattering environment.Integrated on-chip generation of the Bessel beam outperforms the conventional structure by small size,robustness,and alignment-free scheme.However,the maximum propagation distance(Z_(max))provided by the existing approaches cannot support long-range sensing,and thus,it restricts its potential applications.In this work,we propose an integrated silicon photonic chip with unique structures featured with concentrically distributed grating arrays to generate the Bessel-Gaussian beam with a long propagation distance.The spot with the Bessel function profile is measured at 10.24m without optical lenses,and the photonic chip’s operation wavelength can be continuously performed from 1500 to 1630 nm.To demonstrate the functionality of the generated Bessel-Gaussian beam,we also experimentally measure the rotation speeds of a spinning object via the rotational Doppler Effect and the distance through the phase laser ranging principle.The maximum error of the rotation speed in this experiment is measured to be 0.05%,indicating the minimum error in the current reports.By the compact size,low cost,and mass production potential of the integrated process,our approach is promising to readily enable the Bessel-Gaussian beam in widespread optical communication and micro-manipulation applications.
基金National Key Research and Development Program of China(2016YFE0200700)National Natural Science Foundation of China(61627820,61934003,62090054,62105173,62105174)+2 种基金Jilin Scientific and Technological Development Program(20200501007GX)Program for Jilin University Science and Technology Innovative Research Team(JLUSTIRT,2021TD-39)Guangdong Basic and Applied Basic Research Foundation(2019A1515111206)。
文摘Optical phased array(OPA)technology is considered a promising solution for solid-state beam steering to supersede the traditional mechanical beam steering.As a key component of the LIDAR system for long-range detection,OPAs featuring a wide steering angle and high resolution without beam aliasing are highly desired.However,a wide steering range requires a waveguide pitch less than half of the wavelength,which is easily subjected to cross talk.Besides,high resolution requires a large aperture,and it is normally achieved by a high count number of waveguides,which complicates the control system.To solve the mentioned issues,we design two high-performance 128-channel OPAs fabricated on a multilayered SiN-on-SOI platform.Attributed to the nonuniform antenna pitch,only 128 waveguides are used to achieve a 4 mm wide aperture.Besides,by virtue of innovative dual-level silicon nitride(Si_(3)N_(4))waveguide grating antennas,the fishbone antenna OPA achieves a 100°×19.4°field of view(FOV)with divergence of 0.021°×0.029°,and the chain antenna OPA realizes a 140°×19.23°FOV with divergence of 0.021°×0.1°.To our best knowledge,140°is the widest lateral steering range in two-dimensional OPA,and 0.029°is the smallest longitudinal divergence.Finally,we embed the OPA into a frequency-modulated continuous-wave system to achieve 100 m distance measurement.The reflected signal from 100 m distance is well detected with 26 dBm input transmitter power,which proves that OPA serves as a promising candidate for transceiving optical signal in a LIDAR system.
基金supported by the National Natural Science Foundation of China(Nos.61627820,61934003,and62090054)Jilin Scientific and Technological Development Program(No.20200501007GX)Program for Jilin University Science and Technology Innovative Research Team(Nos.JLUSTIRT and 2021TD-39)。
文摘To optimize the dark current characteristic and detection efficiency of the 1550 nm weak light signal at room temperature,this work proposes a Ge-on-Si avalanche photodiode[APD]in Geiger mode,which could operate at 300 K.This lateral separate absorption charge multiplication APD shows a low breakdown voltage[V_(br)]in Geiger mode of-7.42 V and low dark current of 0.096 n A at unity gain voltage[V_(Gain)=1=-7.03 V].Combined with an RF amplifier module and counter,the detection system demonstrates a low dark count rate[DCR]of 1.1×10^(6) counts per second and high detection efficiencyηof 7.8%for 1550 nm weak coherent pulse detection at 300 K.The APD reported in this work weakens the dependence of the weak optical signal recognition on the low environment temperature and makes single-chip integration of the single-photon level detection system possible.
基金Program for Jilin University Science and Technology Innovative Research Team(JLUSTIRT,2021TD-39)Jilin Scientific and Technological Development Program(20200501007GX)National Natural Science Foundation of China(61627820,61934003,62090054)。
文摘Germanium-on-silicon(Ge-on-Si) avalanche photodiodes(APDs) are widely used in near-infrared detection, laser ranging, free space communication, quantum communication, and other fields. However, the existence of lattice defects at the Ge/Si interface causes a high dark current in the Ge-on-Si APD, degrading the device sensitivity and also increasing energy consumption in integrated circuits. In this work, we propose a novel surface illuminated Ge-on-Si APD architecture with three terminals. Besides two electrodes on Si substrates, a third electrode is designed for Ge to regulate the control current and bandwidth, achieving multiple outputs of a single device and reducing the dark current of the device. When the voltage on Ge is -27.5 V, the proposed device achieves a dark current of 100 n A, responsivity of 9.97 A/W at -40 d Bm input laser power at 1550 nm, and optimal bandwidth of 142 MHz. The low dark current and improved responsivity can meet the requirements of autonomous driving and other applications demanding weak light detection.
