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51.
Quantum speed limit (QSL) time under noise has drawn considerable attention in real quantum computational processes. Though non-Markovian noise is found to be able to accelerate quantum evolution for a damped Jaynes-Cummings model, in this work we show that non-Markovianity will slow down the quantum evolution of an experimentally controllable photon system. As an application, QSL time of a photon can be controlled by regulating the relevant environment parameter properly, which nearly reaches the currently available photonic experimental technology. 相似文献
52.
Crystallization kinetics of magnetron-sputtered amorphous TiAl ahoy thin films is investigated by differential scanning calorimetry through isothermal analysis and non-isotherm analysis. In non-isothermai analysis, the Kissinger method and the Ozawa method are used to calculate the apparent activation energy and local activation energy, respectively, in the crystallization processes of amorphous TiA1 thin films. Furthermore, the crystallization mechanism is discussed from the investigation of the A vrami exponent by isothermal analysis. In addition, x-ray diffraction is utilized to reveal the grain orientation and evolution during the crystallization of TiA1 thin fihns. 相似文献
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本文研究了报道了利用化学发光反应动力学曲线进行定量分析的理论,对参加反应物质和催化剂的测定也进行了讨论。 相似文献
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Neurons at rest can exhibit diverse firing activities
patterns in response to various external deterministic and random
stimuli, especially additional currents. In this paper, neuronal
firing patterns from bursting to spiking, induced by additional
direct and stochastic currents, are explored in rest states
corresponding to two values of the parameter $V_{\rm K}$ in the Chay
neuron system. Three cases are considered by numerical simulation
and fast/slow dynamic analysis, in which only the direct current
or the stochastic current exists, or the direct and
stochastic currents coexist. Meanwhile, several important bursting
patterns in neuronal experiments, such as the period-1
``circle/homoclinic" bursting and the integer multiple
``fold/homoclinic" bursting with one spike per burst, as well as
the transition from integer multiple bursting to period-1
``circle/homoclinic" bursting and that from stochastic
``Hopf/homoclinic" bursting to ``Hopf/homoclinic" bursting, are
investigated in detail. 相似文献
59.
在外挂物投放过程中, 载机对外挂物具有气动干扰效应, 产生附加气动力.对于弹性机翼, 在外挂物分离投放时, 相当于给机翼一个初始扰动, 机翼将发生弹性振动, 该振动也会对外挂物带来气动干扰效应.通过耦合求解非定常N-S方程刚体六自由度方程和基于模态法的结构动力学方程, 对考虑弹性变形的载机外挂物分离投放过程进行模拟, 研究了弹性机翼对外挂物的气动干扰效应.研究结果表明:在外挂物分离初期, 弹性机翼的干扰对外挂物气动力响应产生显著影响, 机翼的主要结构模态频率决定了外挂物气动力的变化频率, 并且由载机机翼动弹性变形引起的干扰气动力能占到外挂物总气动力的一半左右. 相似文献
60.
C,igahertz longitudinal acoustic phonons originating from ultrafast ligand field transitions in hematite thin films 下载免费PDF全文
The creation and propagation of longitudinal acoustic phonons (LAPs) in high quality hematite thin films (α-Fe203) epitaxially grown on different substrates (BaTiO3, SrTiO3, and LaAlO3) are investigated using the femtosecond pump- probe technique. Transient reflection measurements (AR/R) indicate the photo-excited electron dynamics, and the initial decay less than 1 ps and the slow decay of -500 ps are attributed to the electron-LO phonon coupling and electron-hole nonradiative recombination, respectively. LAPs in α-Fe2O3 film can be created by ultrafast excitation of the ligand field state, such as the ligand field transitions under 800-nm excitation as well as the ligand to metal charge-transfer with 400- nm excitation. The strain modulations of the sound velocity and the out-of-plane elastic properties are demonstrated in α-Fe2O3 film on different substrates. 相似文献