Break junctions are important in generating nanosensors and single molecular devices. The mechanically con- trollable break junction is the most widely used method for a break junction due to its simplicity and stabil...Break junctions are important in generating nanosensors and single molecular devices. The mechanically con- trollable break junction is the most widely used method for a break junction due to its simplicity and stability. However, the bandwidths of traditional devices are limited to about a few hertz. Moreover, when using traditional methods it is hard to allow independent control of more than one junction. Here we propose on-chip thermally controllable break junctions to overcome these challenges. This is verified by using finite element analysis. Adopting microelectromechanical systems produces features of high bandwidth and independent controllability to this new break junction system. The proposed method will have a wide range of applications on on-chip high speed independent controllable and highly integrated single molecule devices.展开更多
A backside illuminated mesa-structure In Ga As/In P modified uni-traveling-carrier photodiode（MUTC-PD） with wide bandwidth and high saturation power is fabricated and investigated. The device structure is optimized ...A backside illuminated mesa-structure In Ga As/In P modified uni-traveling-carrier photodiode（MUTC-PD） with wide bandwidth and high saturation power is fabricated and investigated. The device structure is optimized to reduce the capacitance and resistance. For the 22-μm-diameter device, the maximum responsivity at 1.55 μm is 0.5 A/W, and the 3-d B cutoff frequency reaches up to 28 GHz. The output photocurrent at the 1-d B compression point is measured to be 54 m A at 25 GHz, with a corresponding output radio frequency（RF） power of up to 15.5 d Bm. The saturation characteristics of the MUTC-PD are also verified by the electric field simulation, and electric field collapse is found to be the cause of the saturation phenomenon.展开更多
随着高带宽需求的不断增长,软件定义网络(Software Defined Networking,SDN)领域内的切片分组网(Slicing Packet Network,SPN)网络架构应运而生。这一架构通过独到的设计,为高速数据传输应用提供了所需的弹性与伸缩能力。然而,针对高带...随着高带宽需求的不断增长,软件定义网络(Software Defined Networking,SDN)领域内的切片分组网(Slicing Packet Network,SPN)网络架构应运而生。这一架构通过独到的设计,为高速数据传输应用提供了所需的弹性与伸缩能力。然而,针对高带宽应用的SPN网络却面临着带宽攻击、数据隐私泄露以及认证与授权管理等问题。文章深入分析这些问题,并提出针对性的解决策略与技术手段。这些解决方案涵盖流量监管、加密防护、隐私保密、身份验证及权力控制等关键领域,并提供一整套安全准则与流量管控技术。展开更多
基金Supported by the National Key Basic Research Program of China under Grant No 2013CB921800the National Natural Science Foundation of China under Grant Nos 11227901,91021005,11274299,11104262 and 10834005the Strategic Priority Research Program(B)of the Chinese Academy of Sciences under Grant No XDB01030400
文摘Break junctions are important in generating nanosensors and single molecular devices. The mechanically con- trollable break junction is the most widely used method for a break junction due to its simplicity and stability. However, the bandwidths of traditional devices are limited to about a few hertz. Moreover, when using traditional methods it is hard to allow independent control of more than one junction. Here we propose on-chip thermally controllable break junctions to overcome these challenges. This is verified by using finite element analysis. Adopting microelectromechanical systems produces features of high bandwidth and independent controllability to this new break junction system. The proposed method will have a wide range of applications on on-chip high speed independent controllable and highly integrated single molecule devices.
基金Project supported by the National Basic Research Program of China(Grant Nos.2012CB315605 and 2014CB340002)the National Natural Science Foundation of China(Grant Nos.61176015,61176059,61210014,61321004,and 61307024)the Open Fund of State Key Laboratory on Integrated Optoelectronics,China(Grant Nos.IOSKL2012KF08 and IOSKL2014KF09)
文摘A backside illuminated mesa-structure In Ga As/In P modified uni-traveling-carrier photodiode（MUTC-PD） with wide bandwidth and high saturation power is fabricated and investigated. The device structure is optimized to reduce the capacitance and resistance. For the 22-μm-diameter device, the maximum responsivity at 1.55 μm is 0.5 A/W, and the 3-d B cutoff frequency reaches up to 28 GHz. The output photocurrent at the 1-d B compression point is measured to be 54 m A at 25 GHz, with a corresponding output radio frequency（RF） power of up to 15.5 d Bm. The saturation characteristics of the MUTC-PD are also verified by the electric field simulation, and electric field collapse is found to be the cause of the saturation phenomenon.
文摘随着高带宽需求的不断增长,软件定义网络(Software Defined Networking,SDN)领域内的切片分组网(Slicing Packet Network,SPN)网络架构应运而生。这一架构通过独到的设计,为高速数据传输应用提供了所需的弹性与伸缩能力。然而,针对高带宽应用的SPN网络却面临着带宽攻击、数据隐私泄露以及认证与授权管理等问题。文章深入分析这些问题,并提出针对性的解决策略与技术手段。这些解决方案涵盖流量监管、加密防护、隐私保密、身份验证及权力控制等关键领域,并提供一整套安全准则与流量管控技术。
