Superconducting microwave resonators play a pivotal role in superconducting quantum circuits.The ability to finetune their resonant frequencies provides enhanced control and flexibility.Here,we introduce a frequency-t...Superconducting microwave resonators play a pivotal role in superconducting quantum circuits.The ability to finetune their resonant frequencies provides enhanced control and flexibility.Here,we introduce a frequency-tunable superconducting coplanar waveguide resonator.By applying electrical currents through specifically designed ground wires,we achieve the generation and control of a localized magnetic field on the central line of the resonator,enabling continuous tuning of its resonant frequency.We demonstrate a frequency tuning range of 54.85 MHz in a 6.21-GHz resonator.This integrated and tunable resonator holds great potential as a dynamically tunable filter and as a key component of communication buses and memory elements in superconducting quantum computing.展开更多
In this paper,we demonstrate a high-sensitivity and real-time heterodyne coherent optical transceiver for intraplane satellite communication,without digital-to-analog converter(DAC)devices and an optical phase lock lo...In this paper,we demonstrate a high-sensitivity and real-time heterodyne coherent optical transceiver for intraplane satellite communication,without digital-to-analog converter(DAC)devices and an optical phase lock loop(OPLL).Based on the scheme,a real-time sensitivity of-49 dBm is achieved at 5 Gbps QPSK.Because DAC is not needed at the transmitter,as well as OPLL at the receiver,this reduces the system cost.Furthermore,the least required Rx ADC bit-width is also discussed.Through theoretical analysis and experimental results,our cost-effective transceiver satisfies the scenario and could be a promising component for future application.展开更多
This paper reports an improved time-delay estimation(TDE)technique for the derivation of turbulence structures based on gas-puff imaging data.The improved TDE technique,integrating an inverse timing search and hierarc...This paper reports an improved time-delay estimation(TDE)technique for the derivation of turbulence structures based on gas-puff imaging data.The improved TDE technique,integrating an inverse timing search and hierarchical strategy,offers superior accuracy in calculating turbulent velocity field maps and analyzing blob dynamics,which has the power to obtain the radial profiles of equilibrium poloidal velocity,blob size and its radial velocity,even the fluctuation analysis,such as geodesic acoustic modes and quasi-coherent mode,etc.This improved technique could provide important 2D information for the study of edge turbulence and blob dynamics,advancing the understanding of edge turbulence physics in fusion plasmas.展开更多
We simulate the measurements of an active bifocal terahertz imaging system to reproduce the ability of the system to detect the internal structure of foams having embedded defects.Angular spectrum theory and geometric...We simulate the measurements of an active bifocal terahertz imaging system to reproduce the ability of the system to detect the internal structure of foams having embedded defects.Angular spectrum theory and geometric optics tracing are used to calculate the incident and received electric fields of the system and the scattered light distribution of the measured object.The finite-element method is also used to calculate the scattering light distribution of the measured object for comparison with the geometric optics model.The simulations are consistent with the measurements at the central axis of the horizontal stripe defects.展开更多
Two-dimensional(2D)semiconductors have attracted considerable interest for their unique physical properties.Here,we report the intrinsic cryogenic electronic transport properties in few-layer MoSe_(2)field-effect tran...Two-dimensional(2D)semiconductors have attracted considerable interest for their unique physical properties.Here,we report the intrinsic cryogenic electronic transport properties in few-layer MoSe_(2)field-effect transistors(FETs)that are fully encapsulated in ultraclean hexagonal boron nitride dielectrics and are simultaneously van der Waals contacted with gold electrodes.The FETs exhibit electronically favorable channel/dielectric interfaces with low densities of interfacial traps(<1010cm^(-2)),which lead to outstanding device characteristics at room temperature,including near-Boltzmann-limit subthreshold swings(65 mV/dec),high carrier mobilities(53–68 cm^(2)·V-1·s^(-1)),and negligible scanning hystereses(<15 mV).The dependence of various contact-related parameters with temperature and carrier density is also systematically characterized to understand the van der Waals contacts between gold and MoSe_(2).The results provide insightful information about the device physics in van der Waals contacted and encapsulated 2D FETs.展开更多
基金supported by the National Natural Science Foundation of China(NSFC,52273206,52173278,and 51833011)Hunan Provincial Natural Science Foundation of China(2021JJ10029,2020JJ3021,and 2021JJ40192)+1 种基金the Open Fund of Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers(E22125)the Science and Technology Innovation Program of Hunan Province(2022RC1075 and 2021RC5028)。
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2021YFA0718802 and 2018YFA0209002)the National Natural Science Foundation of China(Grant Nos.62274086,62288101,61971464,62101243,and 11961141002)+3 种基金the Excellent Young Scholar Program of Jiangsu Province,China(Grant Nos.BK20200008 and BK20200060)the Outstanding Postdoctoral Program of Jiangsu Province,Chinathe Fundamental Research Funds for the Central Universitiesthe Fund from Jiangsu Key Laboratory of Advanced Techniques for Manipulating Electromagnetic Waves。
文摘Superconducting microwave resonators play a pivotal role in superconducting quantum circuits.The ability to finetune their resonant frequencies provides enhanced control and flexibility.Here,we introduce a frequency-tunable superconducting coplanar waveguide resonator.By applying electrical currents through specifically designed ground wires,we achieve the generation and control of a localized magnetic field on the central line of the resonator,enabling continuous tuning of its resonant frequency.We demonstrate a frequency tuning range of 54.85 MHz in a 6.21-GHz resonator.This integrated and tunable resonator holds great potential as a dynamically tunable filter and as a key component of communication buses and memory elements in superconducting quantum computing.
基金supported in part by the National Key Research and Development Program of China(No.2021YFB2900800)the Science and Technology Commission of Shanghai Municipality(Nos.22511100902,22511100502,20511102400,and 20ZR1420900)the 111 Project(No.D20031)。
文摘In this paper,we demonstrate a high-sensitivity and real-time heterodyne coherent optical transceiver for intraplane satellite communication,without digital-to-analog converter(DAC)devices and an optical phase lock loop(OPLL).Based on the scheme,a real-time sensitivity of-49 dBm is achieved at 5 Gbps QPSK.Because DAC is not needed at the transmitter,as well as OPLL at the receiver,this reduces the system cost.Furthermore,the least required Rx ADC bit-width is also discussed.Through theoretical analysis and experimental results,our cost-effective transceiver satisfies the scenario and could be a promising component for future application.
基金partially supported by the National Key R&D Program of China(Nos.2019YFE03030002 and 2022YFE03030001)National Natural Science Foundation of China(Nos.12175186 and 12175055)the Natural Science Foundation of Sichuan Province(Nos.2022NSFSC1820 and 2023NSFSC1289)。
文摘This paper reports an improved time-delay estimation(TDE)technique for the derivation of turbulence structures based on gas-puff imaging data.The improved TDE technique,integrating an inverse timing search and hierarchical strategy,offers superior accuracy in calculating turbulent velocity field maps and analyzing blob dynamics,which has the power to obtain the radial profiles of equilibrium poloidal velocity,blob size and its radial velocity,even the fluctuation analysis,such as geodesic acoustic modes and quasi-coherent mode,etc.This improved technique could provide important 2D information for the study of edge turbulence and blob dynamics,advancing the understanding of edge turbulence physics in fusion plasmas.
基金supported by the National Natural Science Foundation of China(82027802,82171304,82071466,81771260,81871022,82071468,and 82201618)“Sail Plan”Key Medical Specialty(ZYLX202139)+2 种基金“Mission”Talent Project of Beijing Municipal Administration of Hospitals(SML20150802)Beijing Municipal Science and Technology Project(Z181100001918026)Technological Innovation and Service Capability Construction Project From Beijing Municipal Commission of Education(11000023T000002157177)。
基金supported by the National Natural Science Foundation of China(Nos.62227820,62004093,62035014,and 62288101)the Fundamental Research Funds for the Central Universitiesthe Jiangsu Key Laboratory of Advanced Techniques for Manipulating Electromagnetic Waves。
文摘We simulate the measurements of an active bifocal terahertz imaging system to reproduce the ability of the system to detect the internal structure of foams having embedded defects.Angular spectrum theory and geometric optics tracing are used to calculate the incident and received electric fields of the system and the scattered light distribution of the measured object.The finite-element method is also used to calculate the scattering light distribution of the measured object for comparison with the geometric optics model.The simulations are consistent with the measurements at the central axis of the horizontal stripe defects.
基金the National Key R&D Program of China(Grant Nos.2022YFA1203802 and 2021YFA1202903)the National Natural Science Foundation of China(Grant Nos.92264202,61974060,and 61674080)the Innovation and Entrepreneurship Program of Jiangsu Province。
文摘Two-dimensional(2D)semiconductors have attracted considerable interest for their unique physical properties.Here,we report the intrinsic cryogenic electronic transport properties in few-layer MoSe_(2)field-effect transistors(FETs)that are fully encapsulated in ultraclean hexagonal boron nitride dielectrics and are simultaneously van der Waals contacted with gold electrodes.The FETs exhibit electronically favorable channel/dielectric interfaces with low densities of interfacial traps(<1010cm^(-2)),which lead to outstanding device characteristics at room temperature,including near-Boltzmann-limit subthreshold swings(65 mV/dec),high carrier mobilities(53–68 cm^(2)·V-1·s^(-1)),and negligible scanning hystereses(<15 mV).The dependence of various contact-related parameters with temperature and carrier density is also systematically characterized to understand the van der Waals contacts between gold and MoSe_(2).The results provide insightful information about the device physics in van der Waals contacted and encapsulated 2D FETs.