In this work,we achieve high count-rate single-photon output in single-mode(SM)optical fiber.Epitaxial and dilute InAs/GaAs quantum dots(QDs)are embedded in a GaAs/AlGaAs distributed Bragg reflector(DBR)with a micro-p...In this work,we achieve high count-rate single-photon output in single-mode(SM)optical fiber.Epitaxial and dilute InAs/GaAs quantum dots(QDs)are embedded in a GaAs/AlGaAs distributed Bragg reflector(DBR)with a micro-pillar cavity,so as to improve their light emission extraction in the vertical direction,thereby enhancing the optical SM fiber’s collection capabil-ity(numerical aperture:0.13).By tuning the temperature precisely to make the quantum dot exciton emission resonant to the micro-pillar cavity mode(Q~1800),we achieve a fiber-output single-photon count rate as high as 4.73×10^(6) counts per second,with the second-order auto-correlation g2(0)remaining at 0.08.展开更多
Hamamatsu R1924A is one of the most widely used photomultiplier tubes(PMTs) in nuclear physics.Since the active base suitable for R1924A is still not available in market, an active base is designed for Hamamatsu R1924...Hamamatsu R1924A is one of the most widely used photomultiplier tubes(PMTs) in nuclear physics.Since the active base suitable for R1924A is still not available in market, an active base is designed for Hamamatsu R1924A PMT, and the test results at high counting rates are presented. The active bases with two different sets of resistor chains were tested and compared by a frequency-controlled green straw hat LED light. A stable signal output up to 100 kHz is achieved using frequency-controlled LED pulsed light. The temperature of bases, which reflects the power consumption and is crucial for applications in vacuum, is also monitored with the same LED pulsed light. The temperature of the active base with smaller resistances reaches about twice of that of the active base with larger resistances in the resistor chain. For the applications in vacuum, the active base with resistance between the two sets of resistor chains may be preferable.展开更多
The High-energy Fragment Separator(HFRS),which is currently under construction,is a leading international radioactive beam device.Multiple sets of position-sensitive twin time projection chamber(TPC)detectors are dist...The High-energy Fragment Separator(HFRS),which is currently under construction,is a leading international radioactive beam device.Multiple sets of position-sensitive twin time projection chamber(TPC)detectors are distributed on HFRS for particle identification and beam monitoring.The twin TPCs'readout electronics system operates in a trigger-less mode due to its high counting rate,leading to a challenge of handling large amounts of data.To address this problem,we introduced an event-building algorithm.This algorithm employs a hierarchical processing strategy to compress data during transmission and aggregation.In addition,it reconstructs twin TPCs'events online and stores only the reconstructed particle information,which significantly reduces the burden on data transmission and storage resources.Simulation studies demonstrated that the algorithm accurately matches twin TPCs'events and reduces more than 98%of the data volume at a counting rate of 500 kHz/channel.展开更多
钍基熔盐堆(Thorium Molten Salt Reactor,TMSR)是一种第四代反应堆。当反应堆运行时,中子探测环境温度可达550℃以上,因此,中子探测器的应用会受到极大的限制。裂变室(fission chamber)是中子探测器中最重要的类型之一,对高温裂变室(hi...钍基熔盐堆(Thorium Molten Salt Reactor,TMSR)是一种第四代反应堆。当反应堆运行时,中子探测环境温度可达550℃以上,因此,中子探测器的应用会受到极大的限制。裂变室(fission chamber)是中子探测器中最重要的类型之一,对高温裂变室(high temperature fission chamber,HTFC)的研究有助于TMSR测量方案的制定和对中子探测器应用的研究。为此,利用西安脉冲堆和便携式加热器,在17.1~550℃的温度范围内对Photonis的裂变室(型号:CFUE32)进行了实验测量。实验获得了不同温度下,探测器的计数率—电压曲线和脉冲幅度谱。实验结果表明,当温度在450℃以上时,探测器性能有明显的衰退。展开更多
基金supported by the Key-Area Research and Development Program of Guangdong Province(Grant No.2018B030329001)the National Key Technologies R&D Program of China(2018YFA0306101)+2 种基金The Scientific Instrument Developing Project of the Chinese Academy of Science(YJKYYQ20170032)the National Natural Science Foundation of China(61505196)the Program of Beijing Academy of Quantum Information Sciences(Grant No.Y18G01).
文摘In this work,we achieve high count-rate single-photon output in single-mode(SM)optical fiber.Epitaxial and dilute InAs/GaAs quantum dots(QDs)are embedded in a GaAs/AlGaAs distributed Bragg reflector(DBR)with a micro-pillar cavity,so as to improve their light emission extraction in the vertical direction,thereby enhancing the optical SM fiber’s collection capabil-ity(numerical aperture:0.13).By tuning the temperature precisely to make the quantum dot exciton emission resonant to the micro-pillar cavity mode(Q~1800),we achieve a fiber-output single-photon count rate as high as 4.73×10^(6) counts per second,with the second-order auto-correlation g2(0)remaining at 0.08.
基金supported by the National Natural Science Foundation of China(Nos.91426301 and 11075189)the Strategic Priority Research Program of the Chinese Academy of Sciences"ADS project"(No.XDA03030200)+2 种基金the Program for the CAS"Light of West China"(No.29Y601030)the US Department of Energy(No.DE-FG02-93ER40773)the program of the"visiting professorship of senior international scientists of the Chinese Academy of Sciences"for their support during his stay at the IMP
文摘Hamamatsu R1924A is one of the most widely used photomultiplier tubes(PMTs) in nuclear physics.Since the active base suitable for R1924A is still not available in market, an active base is designed for Hamamatsu R1924A PMT, and the test results at high counting rates are presented. The active bases with two different sets of resistor chains were tested and compared by a frequency-controlled green straw hat LED light. A stable signal output up to 100 kHz is achieved using frequency-controlled LED pulsed light. The temperature of bases, which reflects the power consumption and is crucial for applications in vacuum, is also monitored with the same LED pulsed light. The temperature of the active base with smaller resistances reaches about twice of that of the active base with larger resistances in the resistor chain. For the applications in vacuum, the active base with resistance between the two sets of resistor chains may be preferable.
基金partially supported by the Strategic Priority Research Program of Chinese Academy of Science(No.XDB 34030000)the National Natural Science Foundation of China(Nos.11975293 and 12205348)。
文摘The High-energy Fragment Separator(HFRS),which is currently under construction,is a leading international radioactive beam device.Multiple sets of position-sensitive twin time projection chamber(TPC)detectors are distributed on HFRS for particle identification and beam monitoring.The twin TPCs'readout electronics system operates in a trigger-less mode due to its high counting rate,leading to a challenge of handling large amounts of data.To address this problem,we introduced an event-building algorithm.This algorithm employs a hierarchical processing strategy to compress data during transmission and aggregation.In addition,it reconstructs twin TPCs'events online and stores only the reconstructed particle information,which significantly reduces the burden on data transmission and storage resources.Simulation studies demonstrated that the algorithm accurately matches twin TPCs'events and reduces more than 98%of the data volume at a counting rate of 500 kHz/channel.
文摘钍基熔盐堆(Thorium Molten Salt Reactor,TMSR)是一种第四代反应堆。当反应堆运行时,中子探测环境温度可达550℃以上,因此,中子探测器的应用会受到极大的限制。裂变室(fission chamber)是中子探测器中最重要的类型之一,对高温裂变室(high temperature fission chamber,HTFC)的研究有助于TMSR测量方案的制定和对中子探测器应用的研究。为此,利用西安脉冲堆和便携式加热器,在17.1~550℃的温度范围内对Photonis的裂变室(型号:CFUE32)进行了实验测量。实验获得了不同温度下,探测器的计数率—电压曲线和脉冲幅度谱。实验结果表明,当温度在450℃以上时,探测器性能有明显的衰退。