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11.
Anna Zieleniewska Prof. Dr. Dirk M. Guldi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(41):9602-9607
At the focal point of this work is the photophysical characterization of three meso–meso ethene-bridged diporphyrins featuring a diverse metallation pattern. Detailed investigations by means of cyclic voltammetry, absorption, fluorescence, and femto-/nanosecond transient absorption spectroscopy revealed the impact of open-shell nickel(II) on the electronic communication in ethene-bridged heterobimetallic diporphyrins. 相似文献
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《Physics letters. A》2019,383(22):2594-2603
In this work, we address the systematic biases and random errors stemming from finite step sizes encountered in diffusion simulations. We introduce the Effective Geometry Monte Carlo (EG-MC) simulation algorithm which modifies the geometry of the receiver. We motivate our approach in a 1D toy model and then apply our findings to a spherical absorbing receiver in a 3D unbounded environment. We show that with minimal computational cost the impulse response of this receiver can be precisely simulated using EG-MC. Afterwards, we demonstrate the accuracy of our simulations and give tight constraints on the single free parameter in EG-MC. Finally, we comment on the range of applicability of our results. While we present the EG-MC algorithm for the specific case of molecular diffusion, we believe that analogous methods with effective geometry manipulations can be utilized to approach a variety of problems in other branches of physics such as condensed matter physics and cosmological large scale structure simulations. 相似文献
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临近空间相干激光通信链路是天地一体化高速通信网络节点间连接的重要链路。围绕外差效率这一表征大气湍流扰动后信号光和本振光相干合成的指标,推导了非均匀湍流路径上的外差效率理论表达式,并结合大气折射率结构常数廓线,开展了临近空间-地面、临近空间-临近空间和临近空间-低轨卫星三类临近空间相干激光通信链路的外差效率仿真。仿真结果表明:临近空间-低轨卫星链路可以忽略大气对外差效率的影响;如果临近空间-临近空间链路距离大于500 km或是临近空间-地面链路天顶角大于60,外差效率将小于50%,有必要采用自适应光学技术进行补偿。 相似文献
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Four-wave mixing in semiconductor laser amplifiers enables various applications in photonic switching including wavelength conversion, space and time switching, optical phase conjugation, and demultiplexing. Switching times faster than 1 ps are possible. 相似文献
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By analyzing the radiation dose on PIN photodetectors in space radiation environment, the variation of photocurrent and dark current after radiation is obtained. On the basis, the bit error rate of satellite laser communication based on space radiation dose of PIN photodetectors is established. According to simulation, when radiation dose is about 1.6 × 103 Gy and 7 × 104 Gy, bit error rate reaches 10−6 induced by 50 MeV and 10 MeV protons separately; and when radiation dose is within the range of 5 × 10 Gy–6 × 105 Gy, electrons and gamma-ray irradiation also cause increase in bit error rate to 10−6. The principle of damage dose on bit error rate is investigated, and the influence of decision threshold on bit error rate is further discussed. The result shows that when radiation dose is 1 MGy, if decision threshold is increased from 4.3 × 10−7 A to 5.5 × 10−7 A, bit error rate will decrease about 4 orders of magnitude. Hence, a proper decision threshold can improve system bit error rate efficiently. 相似文献
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In laboratory environment, the channel apparatus will generate particular dominant quantum noise. The noise then will give rise to some errors during synchronization. In this work, the accuracies of one qubit transport protocol and entangled states transport protocol in the presence of noise have been studied. With the help of three important and familiar noise models, the quantum noise will degrade the accuracy has been proved. Due to the influence of quantum noise, the accuracy of entangled qubits decrease faster than that of one qubit. The entangled states will improve the accuracy in noise-free channel, and will degrade the accuracy in noise channel. 相似文献
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By swapping the entanglement of genuine four-particle entangled states, we propose a bidirectional quantum secure communication protocol. The biggest merit of this protocol is that the information leakage does not exist. In addition, the ideas of the ``two-step" transmission and the block transmission are employed in this protocol. In order to analyze the security of the second sequence transmission, decoy states are used. 相似文献