A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep aval...A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep avalanche multiplication region for near-infrared(NIR)sensitivity enhancement.By optimizing the device size and electric field of the guard ring,the fill factor(FF)is significantly improved,further increasing photon detection efficiency(PDE).To solve the dark noise caused by the increasing active diameter,a field polysilicon gate structure connected to the p+anode was investigated,effectively suppressing dark count noise by 76.6%.It is experimentally shown that when the active diameter increases from 5 to 10μm,the FF is significantly improved from 20.7%to 39.1%,and thus the peak PDE also rises from 13.3%to 25.8%.At an excess bias voltage of 5 V,a NIR photon detection probability(PDP)of 6.8%at 905 nm,a dark count rate(DCR)of 2.12 cps/μm^(2),an afterpulsing probability(AP)of 1.2%,and a timing jitter of 216 ps are achieved,demonstrating excellent single photon detection performance.展开更多
Planar semiconductor InGaAs/InP single photon avalanche diodes with high responsivity and low dark count rate are preferred single photon detectors in near-infrared communication.However,even with well-designed struct...Planar semiconductor InGaAs/InP single photon avalanche diodes with high responsivity and low dark count rate are preferred single photon detectors in near-infrared communication.However,even with well-designed structures and well-con-trolled operational conditions,the performance of InGaAs/InP SPADs is limited by the inherent characteristics of avalanche pro-cess and the growth quality of InGaAs/InP materials.It is difficult to ensure high detection efficiency while the dark count rate is controlled within a certain range at present.In this paper,we fabricated a device with a thick InGaAs absorption region and an anti-reflection layer.The quantum efficiency of this device reaches 83.2%.We characterized the single-photon performance of the device by a quenching circuit consisting of parallel-balanced InGaAs/InP single photon detectors and single-period sinus-oidal pulse gating.The spike pulse caused by the capacitance effect of the device is eliminated by using the characteristics of parallel balanced common mode signal elimination,and the detection of small avalanche pulse amplitude signal is realized.The maximum detection efficiency is 55.4%with a dark count rate of 43.8 kHz and a noise equivalent power of 6.96×10^(−17 )W/Hz^(1/2) at 247 K.Compared with other reported detectors,this SPAD exhibits higher SPDE and lower noise-equivalent power at a higher cooling temperature.展开更多
This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding type...This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding types on communication performance.The study investigates the impact of on-off keying(OOK)and 2-pulse-position modulation(2-PPM)on the bit error rate(BER)in single-channel intensity and polarization multiplexing.Furthermore,it compares the error correction performance of low-density parity check(LDPC)and Reed-Solomon(RS)codes across different error correction coding types.The effects of unscattered photon ratio and depolarization ratio on BER are also verified.Finally,a UWOC system based on SPD is constructed,achieving 14.58 Mbps with polarization OOK multiplexing modulation and 4.37 Mbps with polarization 2-PPM multiplexing modulation using LDPC code error correction.展开更多
We propose a method of improving the performance of InGaAs/InP avalanche photodiodes by using two avalanche photodiodes in series as single photon detectors for 1550-nm wavelength. In this method, the raw single photo...We propose a method of improving the performance of InGaAs/InP avalanche photodiodes by using two avalanche photodiodes in series as single photon detectors for 1550-nm wavelength. In this method, the raw single photon avalanche signals are not attenuated, thus a high signal-to-noise ratio can be obtained compared with the existing results. The performance of the scheme is investigated and the ratio of the dark count rate to the detection efficiency is obtained to be 1.3×10^-4 at 213 K.展开更多
A reproducible terahertz （THz） photocurrent was observed at low temperatures in a Schottky wrap gate single electron transistor with a normal-incident of a CH3OH gas laser with the frequency 2.54THz. The change of s...A reproducible terahertz （THz） photocurrent was observed at low temperatures in a Schottky wrap gate single electron transistor with a normal-incident of a CH3OH gas laser with the frequency 2.54THz. The change of source-drain current induced by THz photons shows that a satellite peak is generated beside the resonance peak. THz photon energy can be characterized by the difference of gate voltage positions between the resonance peak and satellite peak. This indicates that the satellite peak exactly results from the THz photon-assisted tunneling. Both experimental results and theoretical analysis show that a narrow spacing of double barriers is more effective for the enhancement of THz response.展开更多
Future wireless communication systemembraces physical-layer signal detection with highsensitivity, especially in the microwave photon level.Currently, the receiver primarily adopts the signal detection based on semi-c...Future wireless communication systemembraces physical-layer signal detection with highsensitivity, especially in the microwave photon level.Currently, the receiver primarily adopts the signal detection based on semi-conductor devices for signal detection, while this paper introduces high-sensitivityphoton-level microwave detection based on superconducting structure. We first overview existing works onthe photon-level communication in the optical spectrum as well as the microwave photon-level sensingbased on superconducting structure in both theoreticaland experimental perspectives, including microwavedetection circuit model based on Josephson junction,microwave photon counter based on Josephson junction, and two reconstruction approaches under background noise. In addition, we characterize channelmodeling based on two different microwave photondetection approaches, including the absorption barrierand the dual-path Handury Brown-Twiss (HBT) experiments, and predict the corresponding achievablerates. According to the performance prediction, it isseen that the microwave photon-level signal detectioncan increase the receiver sensitivity compared withthe state-of-the-art standardized communication system with waveform signal reception, with gain over 10dB.展开更多
A near-infrared(NIR) enhanced silicon single-photon avalanche diode(SPAD) detector is proposed using 0.18 μm bipolar-CMOS-DMOS technology. It is based on a deep multiplication region, formed by a junction between the...A near-infrared(NIR) enhanced silicon single-photon avalanche diode(SPAD) detector is proposed using 0.18 μm bipolar-CMOS-DMOS technology. It is based on a deep multiplication region, formed by a junction between the highvoltage P-well(HVPW) and high-voltage buried N+ layer, to enhance the NIR photon detection probability(PDP). Thanks to the lightly doped P-type epitaxial layer, the electric field in the guard ring is reduced and premature breakdown is prevented. In particular, an extra P-type implantation layer(PIL) is added to the HVPW to reduce the breakdown voltage and enhance the device's sensitivity. Further research on the impact of different PIL sizes on the device performance is carried out. It is experimentally shown that at an excess bias voltage of 5 V, the optimized SPAD achieves a dark count rate of 0.64 cps/μm^(2), peak PDP of 54.8% at 555 nm and PDP of 10.53% at 905 nm. The full width at half-maximum of the timing jitter is 285 ps, and the afterpulsing probability is lower than 1.17%. This novel device provides a practical, low-cost solution for high-performance NIR time-of-flight detectors and 3D imaging sensors.展开更多
The quantum fluctuation of photon counting limits the field application of optical time domain reflection. A method of photon counts modulation optics time domain reflection with single photon detection at 1.55 μm is...The quantum fluctuation of photon counting limits the field application of optical time domain reflection. A method of photon counts modulation optics time domain reflection with single photon detection at 1.55 μm is presented. The influence of quantum fluctuation can be effectively controlled by demodulation technology since quantum fluctuation shows a uniform distribution in the frequency domain. Combined with the changing of the integration time of the lock-in amplifier, the signal to noise ratio is significantly enhanced. Accordingly the signal to noise improvement ratio reaches 31.7 dB compared with the direct photon counting measurement.展开更多
In Ga As/In P single photon avalanche diodes（SPADs） are more and more available in many research fields. They are affected by afterpulsing which leads to a poor single photon detection probability. We present an In ...In Ga As/In P single photon avalanche diodes（SPADs） are more and more available in many research fields. They are affected by afterpulsing which leads to a poor single photon detection probability. We present an In Ga As/In P avalanche photodiode with an active quenching circuit on an application specific integrated circuit（ASIC）. It can quench the avalanche rapidly and then reduce the afterpulse rate. Also this quenching circuit can operate in both free-running and gated modes.Furthermore, a new technique is introduced to characterize the influence of the higher order of afterpulses, which uses a program running on a field programmable gate array（FPGA） integrated circuit.展开更多
We demonstrate a mid-infrared superconducting microstrip single-photon detector(SMSPD)based on a 5 nm thick,0.92-μm wide,and 50μm long NbN microbridge.The detection sensitivity is enhanced via He+ion irradiation wit...We demonstrate a mid-infrared superconducting microstrip single-photon detector(SMSPD)based on a 5 nm thick,0.92-μm wide,and 50μm long NbN microbridge.The detection sensitivity is enhanced via He+ion irradiation with a high fluence of 1×10^(17)ions/cm^(2).The SMSPD exhibits saturated internal detection efficiency over a broad spectral range from 400 nm to 5μm at 0.32 K,with a minimum timing jitter of 28 ps(at 1064 nm).The detection current scales with photon energy asα≈`0.5,indicating vortex-assisted hotspot formation as the underlying detection mechanism.展开更多
The study on photon counting statistics is of fundamental importance in quantum optics. We theoretically analyzed the imperfect detection of an arbitrary quantum state. We derived photon counting formulae for six typi...The study on photon counting statistics is of fundamental importance in quantum optics. We theoretically analyzed the imperfect detection of an arbitrary quantum state. We derived photon counting formulae for six typical quantum states （i.e., Fock, coherent, squeeze-vacuum, thermal, odd and even coherent states） with finite quantum efficiencies and dark counts based on multiple on/off detector arrays. We applied the formulae to the simulation of multiphoton number detections and obtained both the simulated and ideal photon number distributions of each state. A comparison between the results by using the fidelity and relative entropy was carried out to evaluate the detection scheme and help select detectors for different quantum states.展开更多
A photon-number-resolving LiDAR approach and an active photon-number-filtering algorithm are proposed and demonstrated.This opens a new avenue for the development of single-photon LiDAR and relevant techniques to scie...A photon-number-resolving LiDAR approach and an active photon-number-filtering algorithm are proposed and demonstrated.This opens a new avenue for the development of single-photon LiDAR and relevant techniques to scientific study and real-world applications.展开更多
Integrated quantum photonics(IQP)allows for on-chip generation,manipulation and detection of quantum states of light,fostering advancements in quantum communication,quantum computing,and quantum information technologi...Integrated quantum photonics(IQP)allows for on-chip generation,manipulation and detection of quantum states of light,fostering advancements in quantum communication,quantum computing,and quantum information technologies.Single-photon detector is a key device in IQP that allows for efficient readout of quantum information through the detection of single-photon statistics and measurement of photonic quantum states.The efficacy of quantum information retrieval hinges on the ability to simultaneously detect every single photon with high efficiency,a relationship that grows exponentially with the number of photons(n).Even a slight decrease in single photon detection efficiency can lead to a significant reduction in probability as n grows larger.Here,we introduce a superconductor-semiconductor heterogeneous integration technology that allows for the integration of transversal superconducting nanowires single-photon detectors that eliminate corner loss on various optical waveguides with exceptional efficiency and versatility.Two cascaded nanowires have been integrated on one silicon waveguide,which not only boosts the detection efficiency to 99.73%at a wavelength of 1550 nm but also provides an on-chip calibration setup,allowing such high efficiency to be measured despite the large loss from fiber-to-waveguide coupling and uncertainties from absolute power calibrations.These advancements represent a substantial improvement compared to previous records,approaching the theoretical limit achievable on silicon waveguide,and demonstrate the versatility of heterogeneous integration technology.This breakthrough in ultra-high detection efficiency establishes a new baseline for assessing quantum measurement capabilities on scalable IQP platforms.展开更多
Collinear laser spectroscopy is a powerful tool for studying the nuclear spins,electromagnetic moments,and charge radii of exotic nuclei.To study the nuclear properties of unstable nuclei at the Beijing Radioactive Io...Collinear laser spectroscopy is a powerful tool for studying the nuclear spins,electromagnetic moments,and charge radii of exotic nuclei.To study the nuclear properties of unstable nuclei at the Beijing Radioactive Ion-beam Facility(BRIF)and the future High Intensity Heavy-ion Accelerator Facility(HIAF),we developed a collinear laser spectroscopy apparatus integrated with an offline laser ablation ion source and a laser system.The overall performance of this state-of-the-art technique was evaluated,and the system was commissioned using a bunched stable ion beam.The high-resolution optical spectra for the 4s ^(2)S_(1/2)→4p^(2)P_(3/2)(D2)ionic transition of ^(40;42;44;48)Ca isotopes were successfully measured.The extracted isotope shifts relative to ^(40)Ca showed excellent agreement with the literature values.This system is now ready for use at radioactive ion beam facilities such as the BRIF and paves the way for the further development of higher-sensitivity collinear resonance ionization spectroscopy techniques.展开更多
A new approach based on microcantilevers is presented to detect infrared photons with high sensitivity. Infrared photons are measured by monitoring the amplitude change of a vibrating microcantilever under light press...A new approach based on microcantilevers is presented to detect infrared photons with high sensitivity. Infrared photons are measured by monitoring the amplitude change of a vibrating microcantilever under light pressure force.The irradiating light is modulated into sinusoidal and pulsed waves,and to be in-phase and anti-phase with the cantilever driving signal.A linear relationship between the amplitude change of the cantilever and the light power distributing on the cantilever was observed.Under a vacuum of 10^（-4） Pa,an infrared light power of 7.4 nW was detected with the cantilever.The in-phase and anti-phase modulation to the cantilever vibration using a pulsed light results in an enhanced response of the cantilever.展开更多
The surface dynamics of supercooled liquid-glycerol is studied by scanning the thickness of the glycerol film with single photon detection. Measurements are performed at room temperature well above the glyeerol＇s gla...The surface dynamics of supercooled liquid-glycerol is studied by scanning the thickness of the glycerol film with single photon detection. Measurements are performed at room temperature well above the glyeerol＇s glass transition temperature. It is shown that the surface dynamics of the glycerol film is very sensitive to the temperature. The linear relationship between the thickness of the film and the viscosity predicted by the Vogel Pulcher-Tammann Hesse （VFTH） law is also presented experimentally.展开更多
The detection of low-level light is a key technology in various experimental scientific studies. As a photon detector, the silicon photomultiplier （SiPM） has gradually become an alternative to the photomultiplier tu...The detection of low-level light is a key technology in various experimental scientific studies. As a photon detector, the silicon photomultiplier （SiPM） has gradually become an alternative to the photomultiplier tube （PMT） in many applications in high-energy physics, astroparticle physics, and medical imaging because of its high photon detection efficiency （PDE）, good resolution for single-photon detection, insensitivity to magnetic field, low operating voltage, compactness, and low cost. However, primarily because of the geometric fill factor, the PDE of most SiPMs is not very high; in particular, for those SiPMs with a high density of micro cells, the effective area is small, and the bandwidth of the light response is narrow. As a building block of the SiPM, the concept of the backside-illuminated avalanche drift detector （ADD） was first proposed by the Max Planck Institute of Germany eight years ago; the ADD is promising to have high PDE over the full energy range of optical photons, even ultraviolet light and X-ray light, and because the avalanche multiplication region is very small, the ADD is beneficial for the fabrication of large-area SiPMs. However, because of difficulties in design and fabrication, no significant progress had been made, and the concept had not yet been verified. In this paper, preliminary results in the design, fabrication, and performance of a backside-illuminated ADD are reported; the difficulties in and limitations to the backside-illuminated ADD are analyzed.展开更多
The influence of the virtual guard ring width(GRW)on the performance of the p-well/deep n-well single-photon avalanche diode(SPAD)in a 180 nm standard CMOS process was investigated.TCAD simulation demonstrates that th...The influence of the virtual guard ring width(GRW)on the performance of the p-well/deep n-well single-photon avalanche diode(SPAD)in a 180 nm standard CMOS process was investigated.TCAD simulation demonstrates that the electric field strength and current density in the guard ring are obviously enhanced when GRW is decreased to 1μm.It is experimentally found that,compared with an SPAD with GRW=2μm,the dark count rate(DCR)and afterpulsing probability(AP)of the SPAD with GRW=1μm is significantly increased by 2.7 times and twofold,respectively,meanwhile,its photon detection probability(PDP)is saturated and hard to be promoted at over 2 V excess bias voltage.Although the fill factor(FF)can be enlarged by reducing GRW,the dark noise of devices is negatively affected due to the enhanced trap-assisted tunneling(TAT)effect in the 1μm guard ring region.By comparison,the SPAD with GRW=2μm can achieve a better trade-off between the FF and noise performance.Our study provides a design guideline for guard rings to realize a low-noise SPAD for large-array applications.展开更多
Wave-particle duality as a fundamental tenet of quantum mechanics is crucial for advancing comprehension of quantum theories and developing quantum technologies with practical applications.However,taking into account ...Wave-particle duality as a fundamental tenet of quantum mechanics is crucial for advancing comprehension of quantum theories and developing quantum technologies with practical applications.However,taking into account experimental impact factors to develop a feasible measurement for wave-like and particle-like properties of light fields is an ongoing challenge,and the non-classicality extraction and determination remains to be explored.In this work,feasibly measurable second-order photon correlations based on Hanbury Brown-Twiss and Hong-Ou-Mandel interferences are employed to analyze the evolution of wave-particle duality for various input states.The wave-particle dualities of chaotic,coherent and mixed classical states as functions of time delay and coherence time are investigated.The realistic impacts of background noise,detection efficiency,intensity ratio and phase differences on the wave-particle duality of nonclassical(Fock and squeezed coherent)states are unveiled.In noisy backgrounds with low detection efficiencies,efficient enhancement and extraction of non-classicality and a continuous transition from classical to nonclassical region are achieved in single photon state mixed with coherent state by adjusting the phase difference from 0 to π/2.The non-classicality of squeezed coherent state can be induced by the classical wave-like and particle-like properties.The research provides a practical precision measurement of wave-particle duality that is helpful for the improvement of high-resolution quantum imaging and sensing.展开更多
In this work,a 4H-SiC-based soft X-ray single photon detector with photon energy resolution capability is demonstrated.The 4H-SiC p-i-n detector with an 80-μm-thick epi-layer and low intrinsic doping exhibits a low l...In this work,a 4H-SiC-based soft X-ray single photon detector with photon energy resolution capability is demonstrated.The 4H-SiC p-i-n detector with an 80-μm-thick epi-layer and low intrinsic doping exhibits a low leakage current of∼1.8 pA at−180 V,guaranteeing superior dark current performance for single photon detection with low electronic noise.An amplification strategy employing an active switch in the charge-sensitive amplifier has also been developed,where feedback-resistance-related thermal noise has been well eliminated,contributing to lower electronic noise in the amplification stage.By tuning the shaping time in the analog-to-digital circuit for precise signal processing,an optimal photon energy resolution has been achieved with a duration time within 6.4µs,achieving an energy analysis standard deviation below 5.7%.Ultimately,superior linearity has been obtained between the output pulse amplitude and the characteristic photon energy by utilizing a series of different metal targets,opening a new opportunity for advanced soft X-ray detection technology based on wide bandgap semiconductors.展开更多
基金supported by the National Natural Science Foundation of China under Grant 62171233the Natural Science Foundation of China,Jiangsu Province under Grant BK20241891the Jiangsu Province Graduate Research and Practice Innovation Plan under Grants SJCX24_0313 and KYCX24_1169。
文摘A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep avalanche multiplication region for near-infrared(NIR)sensitivity enhancement.By optimizing the device size and electric field of the guard ring,the fill factor(FF)is significantly improved,further increasing photon detection efficiency(PDE).To solve the dark noise caused by the increasing active diameter,a field polysilicon gate structure connected to the p+anode was investigated,effectively suppressing dark count noise by 76.6%.It is experimentally shown that when the active diameter increases from 5 to 10μm,the FF is significantly improved from 20.7%to 39.1%,and thus the peak PDE also rises from 13.3%to 25.8%.At an excess bias voltage of 5 V,a NIR photon detection probability(PDP)of 6.8%at 905 nm,a dark count rate(DCR)of 2.12 cps/μm^(2),an afterpulsing probability(AP)of 1.2%,and a timing jitter of 216 ps are achieved,demonstrating excellent single photon detection performance.
基金jointly supported by the National Key Research and Development Program of China (2019YFB22-05202)National Natural Science Foundation of China(61774152)
文摘Planar semiconductor InGaAs/InP single photon avalanche diodes with high responsivity and low dark count rate are preferred single photon detectors in near-infrared communication.However,even with well-designed structures and well-con-trolled operational conditions,the performance of InGaAs/InP SPADs is limited by the inherent characteristics of avalanche pro-cess and the growth quality of InGaAs/InP materials.It is difficult to ensure high detection efficiency while the dark count rate is controlled within a certain range at present.In this paper,we fabricated a device with a thick InGaAs absorption region and an anti-reflection layer.The quantum efficiency of this device reaches 83.2%.We characterized the single-photon performance of the device by a quenching circuit consisting of parallel-balanced InGaAs/InP single photon detectors and single-period sinus-oidal pulse gating.The spike pulse caused by the capacitance effect of the device is eliminated by using the characteristics of parallel balanced common mode signal elimination,and the detection of small avalanche pulse amplitude signal is realized.The maximum detection efficiency is 55.4%with a dark count rate of 43.8 kHz and a noise equivalent power of 6.96×10^(−17 )W/Hz^(1/2) at 247 K.Compared with other reported detectors,this SPAD exhibits higher SPDE and lower noise-equivalent power at a higher cooling temperature.
基金supported in part by the National Natural Science Foundation of China(Nos.62071441 and 61701464)in part by the Fundamental Research Funds for the Central Universities(No.202151006).
文摘This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding types on communication performance.The study investigates the impact of on-off keying(OOK)and 2-pulse-position modulation(2-PPM)on the bit error rate(BER)in single-channel intensity and polarization multiplexing.Furthermore,it compares the error correction performance of low-density parity check(LDPC)and Reed-Solomon(RS)codes across different error correction coding types.The effects of unscattered photon ratio and depolarization ratio on BER are also verified.Finally,a UWOC system based on SPD is constructed,achieving 14.58 Mbps with polarization OOK multiplexing modulation and 4.37 Mbps with polarization 2-PPM multiplexing modulation using LDPC code error correction.
基金Project supported by the National Major Fundamental Research Program of China(Grant No.2006CB921900)the Knowledge Innovation Project of the Chinese Academy of Sciences,and the National Natural Science Foundation of China(Grant Nos.60537020 and 60121503)
文摘We propose a method of improving the performance of InGaAs/InP avalanche photodiodes by using two avalanche photodiodes in series as single photon detectors for 1550-nm wavelength. In this method, the raw single photon avalanche signals are not attenuated, thus a high signal-to-noise ratio can be obtained compared with the existing results. The performance of the scheme is investigated and the ratio of the dark count rate to the detection efficiency is obtained to be 1.3×10^-4 at 213 K.
文摘A reproducible terahertz （THz） photocurrent was observed at low temperatures in a Schottky wrap gate single electron transistor with a normal-incident of a CH3OH gas laser with the frequency 2.54THz. The change of source-drain current induced by THz photons shows that a satellite peak is generated beside the resonance peak. THz photon energy can be characterized by the difference of gate voltage positions between the resonance peak and satellite peak. This indicates that the satellite peak exactly results from the THz photon-assisted tunneling. Both experimental results and theoretical analysis show that a narrow spacing of double barriers is more effective for the enhancement of THz response.
基金National Key Research and Development Program of China(Grant No.2018YFB1801904)Key Program of National Natural Science Foundation of China(Grant No.61631018)Key Research Program of Frontier Sciences of CAS(Grant No.QYZDY-SSW-JSC003).
文摘Future wireless communication systemembraces physical-layer signal detection with highsensitivity, especially in the microwave photon level.Currently, the receiver primarily adopts the signal detection based on semi-conductor devices for signal detection, while this paper introduces high-sensitivityphoton-level microwave detection based on superconducting structure. We first overview existing works onthe photon-level communication in the optical spectrum as well as the microwave photon-level sensingbased on superconducting structure in both theoreticaland experimental perspectives, including microwavedetection circuit model based on Josephson junction,microwave photon counter based on Josephson junction, and two reconstruction approaches under background noise. In addition, we characterize channelmodeling based on two different microwave photondetection approaches, including the absorption barrierand the dual-path Handury Brown-Twiss (HBT) experiments, and predict the corresponding achievablerates. According to the performance prediction, it isseen that the microwave photon-level signal detectioncan increase the receiver sensitivity compared withthe state-of-the-art standardized communication system with waveform signal reception, with gain over 10dB.
基金Project supported by the National Natural Science Foundation of China (Grant No. 62171233)the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20241891)the Jiangsu Province Postgraduate Innovation Program (Grant No. KYCX23_0999)。
文摘A near-infrared(NIR) enhanced silicon single-photon avalanche diode(SPAD) detector is proposed using 0.18 μm bipolar-CMOS-DMOS technology. It is based on a deep multiplication region, formed by a junction between the highvoltage P-well(HVPW) and high-voltage buried N+ layer, to enhance the NIR photon detection probability(PDP). Thanks to the lightly doped P-type epitaxial layer, the electric field in the guard ring is reduced and premature breakdown is prevented. In particular, an extra P-type implantation layer(PIL) is added to the HVPW to reduce the breakdown voltage and enhance the device's sensitivity. Further research on the impact of different PIL sizes on the device performance is carried out. It is experimentally shown that at an excess bias voltage of 5 V, the optimized SPAD achieves a dark count rate of 0.64 cps/μm^(2), peak PDP of 54.8% at 555 nm and PDP of 10.53% at 905 nm. The full width at half-maximum of the timing jitter is 285 ps, and the afterpulsing probability is lower than 1.17%. This novel device provides a practical, low-cost solution for high-performance NIR time-of-flight detectors and 3D imaging sensors.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10674086 and 10934004)the National Natural Science Foundation for Excellent Research Team (Grant No. 60821004)+2 种基金the National Key Basic Research and Development Program of China (Grant No. 2010CB923103)the National High Technology Research and Development Program of China (Grant No. 2009AA01Z319)the Program for Top Science and Technology Innovation Teams and Top Young and Middleaged Innovative Talents of Shanxi Province
文摘The quantum fluctuation of photon counting limits the field application of optical time domain reflection. A method of photon counts modulation optics time domain reflection with single photon detection at 1.55 μm is presented. The influence of quantum fluctuation can be effectively controlled by demodulation technology since quantum fluctuation shows a uniform distribution in the frequency domain. Combined with the changing of the integration time of the lock-in amplifier, the signal to noise ratio is significantly enhanced. Accordingly the signal to noise improvement ratio reaches 31.7 dB compared with the direct photon counting measurement.
基金Project supported by the National Natural Science Foundation of China(Grant No.61178010)the Fundamental Research Funds for the Central Universities,China(Grant No.bupt 2014TS01)+1 种基金the Fund of State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,China(Grant No.201318)the National Program for Basic Research of China(Grant No.2010CB923202)
文摘In Ga As/In P single photon avalanche diodes（SPADs） are more and more available in many research fields. They are affected by afterpulsing which leads to a poor single photon detection probability. We present an In Ga As/In P avalanche photodiode with an active quenching circuit on an application specific integrated circuit（ASIC）. It can quench the avalanche rapidly and then reduce the afterpulse rate. Also this quenching circuit can operate in both free-running and gated modes.Furthermore, a new technique is introduced to characterize the influence of the higher order of afterpulses, which uses a program running on a field programmable gate array（FPGA） integrated circuit.
基金supported by the Quantum Science and Technology-National Science and Technology Major Project(Grant No.2023ZD0300100)the National Natural Science Foundation of China(Grant No.62371443)+3 种基金the Shanghai Sailing Program(Grant No.22YF1456500)the Strategic Priority Research Program(B)of the Chi-nese Academy of Sciences(XDB0580000)the Youth Innovation Promotion Association of CAS(Grant No.2021230)support from the Youth Innovation Promotion Association,CAS(Y2023071)。
文摘We demonstrate a mid-infrared superconducting microstrip single-photon detector(SMSPD)based on a 5 nm thick,0.92-μm wide,and 50μm long NbN microbridge.The detection sensitivity is enhanced via He+ion irradiation with a high fluence of 1×10^(17)ions/cm^(2).The SMSPD exhibits saturated internal detection efficiency over a broad spectral range from 400 nm to 5μm at 0.32 K,with a minimum timing jitter of 28 ps(at 1064 nm).The detection current scales with photon energy asα≈`0.5,indicating vortex-assisted hotspot formation as the underlying detection mechanism.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61627820,11674306,61590932,and 61377048)
文摘The study on photon counting statistics is of fundamental importance in quantum optics. We theoretically analyzed the imperfect detection of an arbitrary quantum state. We derived photon counting formulae for six typical quantum states （i.e., Fock, coherent, squeeze-vacuum, thermal, odd and even coherent states） with finite quantum efficiencies and dark counts based on multiple on/off detector arrays. We applied the formulae to the simulation of multiphoton number detections and obtained both the simulated and ideal photon number distributions of each state. A comparison between the results by using the fidelity and relative entropy was carried out to evaluate the detection scheme and help select detectors for different quantum states.
文摘A photon-number-resolving LiDAR approach and an active photon-number-filtering algorithm are proposed and demonstrated.This opens a new avenue for the development of single-photon LiDAR and relevant techniques to scientific study and real-world applications.
基金supported by the National Natural Science Foundation(Nos.62325105,62227820,62071214,62288101,61571217,and 11227904 and 624B2062)Natural Science Foundation of Jiangsu Province(BK20230020)+3 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0303401)the Fundamental Research Funds for the Central Universitiesthe Jiangsu Provincial Key Laboratory of Advanced Manipulating Technique of Electromagnetic Wavesthe Key Laboratory of Optoelectronic Devices and Systems with Extreme Performances of MOE.
文摘Integrated quantum photonics(IQP)allows for on-chip generation,manipulation and detection of quantum states of light,fostering advancements in quantum communication,quantum computing,and quantum information technologies.Single-photon detector is a key device in IQP that allows for efficient readout of quantum information through the detection of single-photon statistics and measurement of photonic quantum states.The efficacy of quantum information retrieval hinges on the ability to simultaneously detect every single photon with high efficiency,a relationship that grows exponentially with the number of photons(n).Even a slight decrease in single photon detection efficiency can lead to a significant reduction in probability as n grows larger.Here,we introduce a superconductor-semiconductor heterogeneous integration technology that allows for the integration of transversal superconducting nanowires single-photon detectors that eliminate corner loss on various optical waveguides with exceptional efficiency and versatility.Two cascaded nanowires have been integrated on one silicon waveguide,which not only boosts the detection efficiency to 99.73%at a wavelength of 1550 nm but also provides an on-chip calibration setup,allowing such high efficiency to be measured despite the large loss from fiber-to-waveguide coupling and uncertainties from absolute power calibrations.These advancements represent a substantial improvement compared to previous records,approaching the theoretical limit achievable on silicon waveguide,and demonstrate the versatility of heterogeneous integration technology.This breakthrough in ultra-high detection efficiency establishes a new baseline for assessing quantum measurement capabilities on scalable IQP platforms.
基金supported by the National Natural Science Foundation of China(Nos.12027809,U1967201,11875073,11875074 and 11961141003)National Key R&D Program of China(No.2018YFA0404403)+1 种基金China National Nuclear Corporation(No.FA18000201)the State Key Laboratory of Nuclear Physics and Technology,Peking University(No.NPT2019ZZ02).
文摘Collinear laser spectroscopy is a powerful tool for studying the nuclear spins,electromagnetic moments,and charge radii of exotic nuclei.To study the nuclear properties of unstable nuclei at the Beijing Radioactive Ion-beam Facility(BRIF)and the future High Intensity Heavy-ion Accelerator Facility(HIAF),we developed a collinear laser spectroscopy apparatus integrated with an offline laser ablation ion source and a laser system.The overall performance of this state-of-the-art technique was evaluated,and the system was commissioned using a bunched stable ion beam.The high-resolution optical spectra for the 4s ^(2)S_(1/2)→4p^(2)P_(3/2)(D2)ionic transition of ^(40;42;44;48)Ca isotopes were successfully measured.The extracted isotope shifts relative to ^(40)Ca showed excellent agreement with the literature values.This system is now ready for use at radioactive ion beam facilities such as the BRIF and paves the way for the further development of higher-sensitivity collinear resonance ionization spectroscopy techniques.
基金Project supported by the Ministry of Science and Technology of China(Nos.2009CB320305,2011CB933102)
文摘A new approach based on microcantilevers is presented to detect infrared photons with high sensitivity. Infrared photons are measured by monitoring the amplitude change of a vibrating microcantilever under light pressure force.The irradiating light is modulated into sinusoidal and pulsed waves,and to be in-phase and anti-phase with the cantilever driving signal.A linear relationship between the amplitude change of the cantilever and the light power distributing on the cantilever was observed.Under a vacuum of 10^（-4） Pa,an infrared light power of 7.4 nW was detected with the cantilever.The in-phase and anti-phase modulation to the cantilever vibration using a pulsed light results in an enhanced response of the cantilever.
基金supported by the Natural Science Foundation of China (Grant No 10674086)973 Program of China (Grant Nos 2006CB921603,2006CB921102 and 2008CB317103)+4 种基金863 Program of China (Grant No 2009AA01Z319)NCET-06-0259the Shanxi Provincial Foundation for Leaders of Disciplines in Sciencethe Natural Science Foundation of Shanxi province,China (Grant No 2007011006)Shanxi Province Foundation for Returned scholars of China
文摘The surface dynamics of supercooled liquid-glycerol is studied by scanning the thickness of the glycerol film with single photon detection. Measurements are performed at room temperature well above the glyeerol＇s glass transition temperature. It is shown that the surface dynamics of the glycerol film is very sensitive to the temperature. The linear relationship between the thickness of the film and the viscosity predicted by the Vogel Pulcher-Tammann Hesse （VFTH） law is also presented experimentally.
基金Project supported by the National Natural Science Foundation of China(Grant No.11005010)
文摘The detection of low-level light is a key technology in various experimental scientific studies. As a photon detector, the silicon photomultiplier （SiPM） has gradually become an alternative to the photomultiplier tube （PMT） in many applications in high-energy physics, astroparticle physics, and medical imaging because of its high photon detection efficiency （PDE）, good resolution for single-photon detection, insensitivity to magnetic field, low operating voltage, compactness, and low cost. However, primarily because of the geometric fill factor, the PDE of most SiPMs is not very high; in particular, for those SiPMs with a high density of micro cells, the effective area is small, and the bandwidth of the light response is narrow. As a building block of the SiPM, the concept of the backside-illuminated avalanche drift detector （ADD） was first proposed by the Max Planck Institute of Germany eight years ago; the ADD is promising to have high PDE over the full energy range of optical photons, even ultraviolet light and X-ray light, and because the avalanche multiplication region is very small, the ADD is beneficial for the fabrication of large-area SiPMs. However, because of difficulties in design and fabrication, no significant progress had been made, and the concept had not yet been verified. In this paper, preliminary results in the design, fabrication, and performance of a backside-illuminated ADD are reported; the difficulties in and limitations to the backside-illuminated ADD are analyzed.
基金supported by the Jiangsu Agricultural Science and Technology Innovation Fund of China(No.CX(21)3062)the National Natural Science Foundation of China(No.62171233).
文摘The influence of the virtual guard ring width(GRW)on the performance of the p-well/deep n-well single-photon avalanche diode(SPAD)in a 180 nm standard CMOS process was investigated.TCAD simulation demonstrates that the electric field strength and current density in the guard ring are obviously enhanced when GRW is decreased to 1μm.It is experimentally found that,compared with an SPAD with GRW=2μm,the dark count rate(DCR)and afterpulsing probability(AP)of the SPAD with GRW=1μm is significantly increased by 2.7 times and twofold,respectively,meanwhile,its photon detection probability(PDP)is saturated and hard to be promoted at over 2 V excess bias voltage.Although the fill factor(FF)can be enlarged by reducing GRW,the dark noise of devices is negatively affected due to the enhanced trap-assisted tunneling(TAT)effect in the 1μm guard ring region.By comparison,the SPAD with GRW=2μm can achieve a better trade-off between the FF and noise performance.Our study provides a design guideline for guard rings to realize a low-noise SPAD for large-array applications.
基金supported by the National Key Research and Development Program of China(No.2022YFA1404201)the National Natural Science Foundation of China(Nos.62175176,62075154,62475185,U23A20380,and 62305241)the Natural Science Foundation of Shanxi Province(Nos.202203021222107 and 202203021222113).
文摘Wave-particle duality as a fundamental tenet of quantum mechanics is crucial for advancing comprehension of quantum theories and developing quantum technologies with practical applications.However,taking into account experimental impact factors to develop a feasible measurement for wave-like and particle-like properties of light fields is an ongoing challenge,and the non-classicality extraction and determination remains to be explored.In this work,feasibly measurable second-order photon correlations based on Hanbury Brown-Twiss and Hong-Ou-Mandel interferences are employed to analyze the evolution of wave-particle duality for various input states.The wave-particle dualities of chaotic,coherent and mixed classical states as functions of time delay and coherence time are investigated.The realistic impacts of background noise,detection efficiency,intensity ratio and phase differences on the wave-particle duality of nonclassical(Fock and squeezed coherent)states are unveiled.In noisy backgrounds with low detection efficiencies,efficient enhancement and extraction of non-classicality and a continuous transition from classical to nonclassical region are achieved in single photon state mixed with coherent state by adjusting the phase difference from 0 to π/2.The non-classicality of squeezed coherent state can be induced by the classical wave-like and particle-like properties.The research provides a practical precision measurement of wave-particle duality that is helpful for the improvement of high-resolution quantum imaging and sensing.
基金supported by the Innovation Program for Quantum Science and Technology(No.2021ZD0303400)the National Natural Science Foundation of China(Nos.62374084,61921005,62104102,U2141241,and U21A20496)+1 种基金the Jiangsu Provincial Key Research and Development Program(No.BE2023018)the Fundamental Research Funds for the Central Universities.
文摘In this work,a 4H-SiC-based soft X-ray single photon detector with photon energy resolution capability is demonstrated.The 4H-SiC p-i-n detector with an 80-μm-thick epi-layer and low intrinsic doping exhibits a low leakage current of∼1.8 pA at−180 V,guaranteeing superior dark current performance for single photon detection with low electronic noise.An amplification strategy employing an active switch in the charge-sensitive amplifier has also been developed,where feedback-resistance-related thermal noise has been well eliminated,contributing to lower electronic noise in the amplification stage.By tuning the shaping time in the analog-to-digital circuit for precise signal processing,an optimal photon energy resolution has been achieved with a duration time within 6.4µs,achieving an energy analysis standard deviation below 5.7%.Ultimately,superior linearity has been obtained between the output pulse amplitude and the characteristic photon energy by utilizing a series of different metal targets,opening a new opportunity for advanced soft X-ray detection technology based on wide bandgap semiconductors.
