修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

5 条数据
?? 中文(中国)
  • Minimal Timing Jitter in Superconducting Nanowire Single-Photon Petectors

    摘要: Using a two-temperature model coupled with the modified time-dependent Ginzburg-Landau equation, we calculate the delay time τd in the appearance of a growing normal domain in the current-biased superconducting strip after absorption of the single photon. We demonstrate that τd depends on the place in the strip where the photon is absorbed and monotonically decreases with an increasing current. We argue that the variation of τd (timing jitter), connected either with position-dependent response or Fano fluctuations, could be as small as the lowest relaxation time of the superconducting order parameter, approximately ?/kBTc (Tc is the critical temperature of the superconductor), when the current approaches the depairing current.

    关键词: position-dependent response,timing jitter,superconducting nanowire single-photon detectors,delay time,Fano fluctuations

    更新于2025-09-23 15:23:52

  • [IEEE 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Novosibirsk, Russia (2018.10.2-2018.10.6)] 2018 XIV International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE) - Synthesis of Group Delay Time Correctors on the Basis of Two Types Directional Couplers

    摘要: A group delay time correctors on the basis of contra-directional and trans-directional couplers are considered. The formulas for calculating the frequency characteristics of the load resistors forming a given frequency dependence of the phase and group delay time are obtained.

    关键词: Synthesis,directional couplers based on coupled strip lines,group delay time correctors

    更新于2025-09-23 15:23:52

  • A Cyclic TDC using Variable Delay Circuit

    摘要: A cyclic TDC can be implemented in a small area with high resolution but it takes long conversion time. To reduce a conversion time, we introduce variable delay circuits that can change a delay time of a pulse. We also introduce calibration techniques, an offset cancellation and delay matching, to improve linearity of the TDC. We confirmed through circuit simulation that the proposed circuit achieves a time resolution of 9.38 ps, dynamic range of 18.7 ns, sampling rate of 2 MS/s, and a power consumption of 11 mW at 1.8 V operation.

    关键词: variable delay,Time-to-Digital Converter,calibration,cyclic,Multiple Delay inverter

    更新于2025-09-23 15:22:29

  • New Method for Studying the Ignition Characteristics of Condensed Systems by Laser Radiation

    摘要: A method for determining the characteristics of laser ignition of the condensed systems is presented, which ensures uniform distribution of the heat flux density over the surface during ignition. The method consists in measuring the ignition delay time of a rotating cylindrical sample when the continuous laser heat flux is applied to its end surface. The theoretical estimation of the required angular rotation velocity of the sample is carried out, which ensures averaging with a given error of the radiation flux density on the surface of the sample, as well as the degree of surface cooling due to the convective heat transfer. The experimental results on the pyroxylin sample ignition at the radiant heating by a CO2 laser with and without rotation of the sample are presented.

    关键词: pyroxylin,laser ignition,ignition delay time,condensed system,convective heat transfer,angular velocity of rotation

    更新于2025-09-23 15:19:57

  • Ignition of Hydrocarbon–Oxygen Mixtures by Means of a Nanosecond Surface Dielectric Barrier Discharge

    摘要: Ignition of hydrocarbon–oxygen mixtures by means of a nanosecond surface dielectric barrier discharge (NSDBD) was studied experimentally. The propagation velocity of the flame wave and the ignition delay time in mixtures of oxygen with methane, ethane, ethylene, and dimethyl ether were measured using a high-speed camera. The experiments were carried out at room temperature and gas mixture pressures in the range of 0.75–1.25 atm. It is shown that, for all hydrocarbons under study, the flame velocity decreases with reducing pressure and stoichiometric ratio, as well as when the mixture is diluted with molecular nitrogen. Theoretical analysis of the processes in the NSDBD plasma and measurements of the flame velocity in hydrocarbon-containing mixtures without plasma agree qualitatively with the measurement results, except for the increasing dependence of the flame velocity on the pressure, which is decreasing in experiments without a discharge plasma.

    关键词: ignition,nanosecond surface dielectric barrier discharge,flame velocity,ignition delay time,hydrocarbon–oxygen mixtures

    更新于2025-09-10 09:29:36