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31.
Reference-frame-independent quantum key distribution of wavelength division multiplexing with multiple quantum channels 下载免费PDF全文
Zhongqi Sun 《中国物理 B》2021,30(11):110303-110303
Reference-frame-independent quantum key distribution (RFI-QKD) can allow a quantum key distribution system to obtain the ideal key rate and transmission distance without reference system calibration, which has attracted much attention. Here, we propose an RFI-QKD protocol based on wavelength division multiplexing (WDM) considering finite-key analysis and crosstalk. The finite-key bound for RFI-QKD with decoy states is derived under the crosstalk of WDM. The resulting secret key rate of RFI-QKD, which is more rigorous, is obtained. Simulation results reveal that the secret key rate of RFI-QKD based on WDM is affected by the multiplexing channel number, as well as crosstalk between adjacent channels. 相似文献
32.
Electronic and optical properties of 3N-doped graphdiyne/MoS2 heterostructures tuned by biaxial strain and external electric field 下载免费PDF全文
The construction of van der Waals (vdW) heterostructures by stacking different two-dimensional layered materials have been recognised as an effective strategy to obtain the desired properties. The 3N-doped graphdiyne (N-GY) has been successfully synthesized in the laboratory. It could be assembled into a supercapacitor and can be used for tensile energy storage. However, the flat band and wide forbidden bands could hinder its application of N-GY layer in optoelectronic and nanoelectronic devices. In order to extend the application of N-GY layer in electronic devices, MoS2 was selected to construct an N-GY/MoS2 heterostructure due to its good electronic and optical properties. The N-GY/MoS2 heterostructure has an optical absorption range from the visible to ultraviolet with a absorption coefficient of 105 cm-1. The N-GY/MoS2 heterostructure exhibits a type-Ⅱ band alignment allows the electron-hole to be located on N-GY and MoS2 respectively, which can further reduce the electron-hole complexation to increase exciton lifetime. The power conversion efficiency of N-GY/MoS2 heterostructure is up to 17.77%, indicating it is a promising candidate material for solar cells. In addition, the external electric field and biaxial strain could effectively tune the electronic structure. Our results provide a theoretical support for the design and application of N-GY/MoS2 vdW heterostructures in semiconductor sensors and photovoltaic devices. 相似文献
33.
Ultra-longer fiber cantilever taper for simultaneous measurement of temperature and relative humidity 下载免费PDF全文
An ultra-longer fiber cantilever taper for simultaneous measurement of the temperature and relative humidity (RH) with high sensitivities was proposed. The structure was fabricated by using the simple and cost-effective method only including fiber cleaving, splicing, and tapering. The length of the cantilever taper is about 1.5 mm. The dip A and dip B were measured simultaneously, owing to the ultra-long length and super-fine size, the temperature sensitivities of the dip A and dip B reached as high as 127.3 pm/℃ and 0 pm/℃ between 25 ℃ and 50 ℃, and the RH sensitivities are -31.2 pm/% RH and -29.2 pm/% RH with a broad RH interval ranging from 20% RH to 70% RH. Besides, the proposed structure showed good linearity in the sensing process and small temperature crosstalk. It will be found in wide applications in environmental monitoring, food processing, and industries. 相似文献
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在强光一号装置开展小倾角单层锥形钨丝阵实验, 获得了锥形丝阵在消融阶段, 拉链内爆阶段和滞止阶段的辐射参数和辐射图像. 消融阶段的物理图像映证了使用火箭模型对锥形丝阵消融过程及先驱等离子体形成的分析. 结合分幅像、针孔像和条纹像, 解释了锥形丝阵在内爆箍缩阶段阴极部分首先发生内爆并产生硬X射线成分的原因. 观察到的锥形丝阵的拉链内爆速度达到2.59× 107 cm/s, 拉链内爆及滞止的持续时间达到40 ns, 远大于相近尺寸的柱形丝阵. 通过特殊构型丝阵内爆特性的研究, 为进一步验证基于柱形丝阵建立的Z-pinch理论模型, 完善MHD模型的普适性提供必要的实验数据. 相似文献
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利用三维粒子模拟仿真软件,对共焦波导结构的0.4 THz回旋行波管进行了注波互作用的模拟研究。以共焦波导的冷腔色散以及衍射损耗入手,最终选定HE06模作为互作用工作模式。为了对寄生振荡进行抑制,在互作用结构中引入了截断。在模拟过程中,通过调节束压、束流、工作磁场、电子束横纵速度比,得到了最优的工作参数。最终,在束压34 kV、磁场14.25、束流2 A、横纵速度比0.75的工作参数下,当输入信号为1 W时,得到了最高2.76 kW的功率输出,增益超过34 dB,3 dB带宽为8 GHz,效率达到4%。 相似文献
40.
The reflection properties of planar anisotropy Fe50Ni50 powder/paraffin composites have been studied in the microwave frequency range.The permeability of Fe50Ni50 powder/paraffin composites is greatly enhanced by introducing the planar anisotropy,and can be further enhanced by using a rotational orientation method.The complex permeability can be considered as the superposition of two types of magnetic resonance.The resonance peak at high frequency is attributed to the natural resonance,while the peak at low frequency is attributed to the domain-wall resonance.The simulated results of the microwave reflectivity show that the matching thickness,peak frequency,permeability,and permittivity are closely related to the quarter wavelength matching condition.The Fe50Ni50 powder/paraffin composites can be attractive candidates for thinner microwave absorbers in the L-band(1-2 GHz). 相似文献