As the demand for energy efficiency rises,researchers are increasingly prioritizing the quest for energy-efficient chip design.Superconducting SFQ circuit technology has garnered attention due to its ultra-high speed ...As the demand for energy efficiency rises,researchers are increasingly prioritizing the quest for energy-efficient chip design.Superconducting SFQ circuit technology has garnered attention due to its ultra-high speed and low power consumption characteristics.In this paper,we propose a layout method called Maximum Operating Frequency Constraint(MOFC)for SFQ circuit design.Using this method,we demonstrated a 32-bit bit-parallel string-matching processor fabricated based on SIMIT-Nb03P technology,which holds practical value.The MOFC method focuses on achieving high bit-width processor design within constrained area cost in SFQ circuits,contributing to less energy consumption.To the best of our knowledge,this represents the first demonstrated instance of a superconducting SFQ chip achieving successful internal 32-bit data parallel processing.Our chip has been fabricated and tested,revealing not only its capability for 32-bit bit-parallel processing at a high speed of 12 GHz but also its achievement of an energy efficiency ratio of up to 251 GOPS/W.展开更多
Rapid single flux quantum(RSFQ)circuits have the advantages of high speed and low power consumption.The typical frequency of the RSFQ circuits is tens of GHz.Therefore,it is necessary to reliably test the highfrequenc...Rapid single flux quantum(RSFQ)circuits have the advantages of high speed and low power consumption.The typical frequency of the RSFQ circuits is tens of GHz.Therefore,it is necessary to reliably test the highfrequency performance of RSFQ circuits simply and effectively.This paper proposes a new on-chip highfrequency testing method,which uses pseudo-random sequences generated by linear feedback shift register(LFSR)as the test vectors,and the output shift registers(SRs)to store the last piece of high-frequency testing result and read out it at low-frequency.Unlike the traditional high-frequency demonstration method of using the Input/Output SRs,our testing system can automatically generate a large number of test vectors to test the circuit at high frequency at low cost,making the whole high-frequency demonstration more reliable and convincing.On the other hand,this method is also a feasible and straightforward on-chip high-frequency test method for various RSFQ circuits.This work verified the proposed method,and the highest test frequency can reach 54 GHz while the circuit shows good operating margins.展开更多
随机公平队列(Stochastic Fairness Queueing,SFQ)是一种典型的公平队列调度算法。UDP洪流是实施DDoS攻击的一种主要攻击手段。研究了SFQ调度和网络中广泛应用的先到先服务(First Come First Server,FCFS)队列调度策略对UDP洪流攻击的...随机公平队列(Stochastic Fairness Queueing,SFQ)是一种典型的公平队列调度算法。UDP洪流是实施DDoS攻击的一种主要攻击手段。研究了SFQ调度和网络中广泛应用的先到先服务(First Come First Server,FCFS)队列调度策略对UDP洪流攻击的抑制效果。基于多协议网络模拟平台NS2的仿真结果表明,FCFS调度难以对UDP洪流攻击产生有效的抑制作用,而SFQ调度却能在一定程度上抑制该攻击。展开更多
We propose a scheme for generating squeezed states based on a superconducting hybrid system. Our system consists of a nanomeehanical resonator, a superconducting flux qubit, and a superconducting transmission line res...We propose a scheme for generating squeezed states based on a superconducting hybrid system. Our system consists of a nanomeehanical resonator, a superconducting flux qubit, and a superconducting transmission line resonator. Using our proposal, one can easily generate the squeezed states of the nanomechanical resonator. In our scheme, the nonlinear interaction between the nanomechanical resonator and the superconducting transmission line resonator can be implemented by the flux qubit as ＇nonlinear media＇ with a tunable Josephson energy. The realization of the nonlinearity does not need any operations on the flux qubit and just needs to adiabatically keep it at the ground state, which can greatly decrease the effect of the decoherenee of the flux qubit on the squeezed ef^ciency.展开更多
Single-flux-quantum(SFQ)circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors.SFQ-based quantum gates have been designed and realized.Howeve...Single-flux-quantum(SFQ)circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors.SFQ-based quantum gates have been designed and realized.However,current control schemes are difficult to tune the driving strength to qubits,which restricts the gate length and usually induces leakage to unwanted levels.In this study,we design the scheme and corresponding pulse generator circuit to continuously adjust the driving strength by coupling SFQ pulses with variable intervals.This scheme not only provides a way to adjust the SFQ-based gate length,but also proposes the possibility to tune the driving strength envelope.Simulations show that our scheme can suppress leakage to unwanted levels and reduce the error of SFQ-based Clifford gates by more than an order of magnitude.展开更多
文摘As the demand for energy efficiency rises,researchers are increasingly prioritizing the quest for energy-efficient chip design.Superconducting SFQ circuit technology has garnered attention due to its ultra-high speed and low power consumption characteristics.In this paper,we propose a layout method called Maximum Operating Frequency Constraint(MOFC)for SFQ circuit design.Using this method,we demonstrated a 32-bit bit-parallel string-matching processor fabricated based on SIMIT-Nb03P technology,which holds practical value.The MOFC method focuses on achieving high bit-width processor design within constrained area cost in SFQ circuits,contributing to less energy consumption.To the best of our knowledge,this represents the first demonstrated instance of a superconducting SFQ chip achieving successful internal 32-bit data parallel processing.Our chip has been fabricated and tested,revealing not only its capability for 32-bit bit-parallel processing at a high speed of 12 GHz but also its achievement of an energy efficiency ratio of up to 251 GOPS/W.
基金supported by the National Natural Science Foundation of China under Grant No.92164101the National Natural Science Foundation of China under Grant No.62171437+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No.XDA18000000Shanghai Science and Technology Committee(Grant No.21DZ1101000)the National Key R&D Program of China under Grant No.2021YFB0300400.
文摘Rapid single flux quantum(RSFQ)circuits have the advantages of high speed and low power consumption.The typical frequency of the RSFQ circuits is tens of GHz.Therefore,it is necessary to reliably test the highfrequency performance of RSFQ circuits simply and effectively.This paper proposes a new on-chip highfrequency testing method,which uses pseudo-random sequences generated by linear feedback shift register(LFSR)as the test vectors,and the output shift registers(SRs)to store the last piece of high-frequency testing result and read out it at low-frequency.Unlike the traditional high-frequency demonstration method of using the Input/Output SRs,our testing system can automatically generate a large number of test vectors to test the circuit at high frequency at low cost,making the whole high-frequency demonstration more reliable and convincing.On the other hand,this method is also a feasible and straightforward on-chip high-frequency test method for various RSFQ circuits.This work verified the proposed method,and the highest test frequency can reach 54 GHz while the circuit shows good operating margins.
文摘随机公平队列(Stochastic Fairness Queueing,SFQ)是一种典型的公平队列调度算法。UDP洪流是实施DDoS攻击的一种主要攻击手段。研究了SFQ调度和网络中广泛应用的先到先服务(First Come First Server,FCFS)队列调度策略对UDP洪流攻击的抑制效果。基于多协议网络模拟平台NS2的仿真结果表明,FCFS调度难以对UDP洪流攻击产生有效的抑制作用,而SFQ调度却能在一定程度上抑制该攻击。
基金Supported by the National Natural Science Foundation of China under Grant Nos 11274043 and 60978009the Major Research Plan of the National Natural Science Foundation of China under Grant No 91121023
文摘We propose a scheme for generating squeezed states based on a superconducting hybrid system. Our system consists of a nanomeehanical resonator, a superconducting flux qubit, and a superconducting transmission line resonator. Using our proposal, one can easily generate the squeezed states of the nanomechanical resonator. In our scheme, the nonlinear interaction between the nanomechanical resonator and the superconducting transmission line resonator can be implemented by the flux qubit as ＇nonlinear media＇ with a tunable Josephson energy. The realization of the nonlinearity does not need any operations on the flux qubit and just needs to adiabatically keep it at the ground state, which can greatly decrease the effect of the decoherenee of the flux qubit on the squeezed ef^ciency.
基金Project supported in part by the National Natural Science Foundation of China (Grant No.92065116)the Key-Area Research and Development Program of Guangdong Province,China (Grant No.2020B0303030002)+1 种基金the Shanghai Technology Innovation Action Plan Integrated Circuit Technology Support Program (Grant No.22DZ1100200)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDA18000000)。
文摘Single-flux-quantum(SFQ)circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors.SFQ-based quantum gates have been designed and realized.However,current control schemes are difficult to tune the driving strength to qubits,which restricts the gate length and usually induces leakage to unwanted levels.In this study,we design the scheme and corresponding pulse generator circuit to continuously adjust the driving strength by coupling SFQ pulses with variable intervals.This scheme not only provides a way to adjust the SFQ-based gate length,but also proposes the possibility to tune the driving strength envelope.Simulations show that our scheme can suppress leakage to unwanted levels and reduce the error of SFQ-based Clifford gates by more than an order of magnitude.
