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101.
102.
《Physics letters. A》2020,384(1):126039
Different from the conventional Rydberg antiblockade (RAB) regime that either requires weak Rydberg-Rydberg interaction (RRI), or compensates the RRI-induced energy shift by introducing off-resonant interactions, we show that RAB regime can be achieved by resonantly driving the transitions between ground state and Rydberg state under strong RRI. The Rabi frequencies are of small amplitude and time-dependent harmonic oscillation, which plays a critical role for the presented RAB. The proposed unconventional RAB regime is used to construct high-fidelity controlled-Z (CZ) gate and controlled-not (CNOT) gate in one step. Each atom requires single external driving. And the atomic addressability is not required for the presented unconventional RAB, which would simplify experimental complexity and reduce resource consumption. 相似文献
103.
104.
The melting of isothermally crystallized poly(vinylidene fluoride) (PVF2), produced in the intercrystalline spaces of poly(ethylene terephthalate) (PET) from its blends, showed a unique behavior: the melting temperature decreased with the increasing crystallinity of PVF2 (i.e., with increasing crystallization time) for PVF2 volume fractions of 0.64 and 0.51. The melting temperature of already crystallized PET also decreased as the PVF2 crystallization progressed and the isothermal crystallization temperature of PVF2 increased. Separate reasons were proposed to account for these behaviors. The equilibrium melting temperatures of PVF2 in the blends, measured by the Hoffman–Weeks extrapolation procedure, were used to calculate the polymer–polymer interaction parameter (χ21); only the noncrystallized portion of PET contributing to the mixed amorphous phase was considered. The χ21value (−1.75) was lower than χ12 (−0.14), calculated from the melting temperature depression of PET. However, when they were normalized to the unit volumes of the respective components, the two values were found to be the same. The crystallization rate of PVF2 decreased with an increasing volume fraction of PET in the blend. The Avrami exponent increased for the volume fraction of PVF2 (0.77) and then progressively decreased with an increasing volume fraction of PET. A gradual change in the nature of the regime transition from regime II/regime I to regime III/regime II with increasing PET concentration was observed. The value of the chain-extension factor of PVF2 significantly increased with an increase in the PET concentration in the blends. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2215–2227, 2004 相似文献
105.
Quantitative results for the thrust and flow-rate performance of axisymmetric nozzles in highly overexpanded regimes are presented. Estimates for the lateral component of the reactive force and its range of possible existence are obtained for axisymmetric nozzles differing in the divergent region geometry. Empirical formulas for the gas flow rate in the subcritical outflow regime and the pressure range on which this regime can take place are proposed. 相似文献
106.
This paper describes flow around a pair of cylinders in tandem arrangement with a downstream cylinder being fixed or forced to oscillate transversely. A sinusoidal parietal velocity is applied to simulate cylinder oscillation. Time-dependent Navier-Stokes equations are solved using finite element method. It is shown that there exist two distinct flow regimes: ‘vortex suppression regime’ and ‘vortex formation regime’. Averaged vortex lengths between the two cylinders, pressure variations at back and front stagnant points as well as circumferential pressure profiles of the downstream cylinder are found completely different in the two regimes and, thus, can be used to identify the flow regimes. It is shown that frequency selection in the wake of the oscillating cylinder is a result of non-linear interaction among vortex wakes upstream and downstream of the second cylinder and its forced oscillation. Increasing cylinder spacing results in a stronger oscillatory incident flow upstream of the second cylinder and, thus, a smaller synchronization zone. 相似文献
107.
The operation of an ambipolar field‐effect transistor (FET) is described using a simple diagram depicting the gate voltage and channel potential profile relative to the injection threshold voltage of charge carriers. From this diagram, the transition between transistor‐operation regimes and the resulting current–voltage relations can be easily understood. Also, a practical guidance for the operation of an ambipolar FET is provided. In particular, conditions to achieve the true ambipolar regime, which is of particular interest for light‐emitting transistor operation, and a correct method to extract electron and hole mobilities from a given current–voltage curve are presented. 相似文献
108.
Moncef Aouadi 《Acta Appl Math》2009,106(2):307-323
In this paper we derive some spatial stability results for the quasi-static problem in thermoelastic diffusion theory for
anisotropic media. The coupled system of equations of thermoelasticity with diffusion is a coupling of an elliptic equation
with two parabolic equations. It poses some new mathematical difficulties. Here we study the exponential spatial decay of
solutions. An upper bound for the amplitude in terms of the boundary and initial conditions is obtained. The extension of
the spatial stability results is also treated. 相似文献
109.
利用激光脉冲在光纤中传播时所遵守的相干非线性薛定谔耦合方程,研究了保偏光纤中两相近频率的线偏振光,其偏振方向相互正交且平行于光纤的双折射轴,且偏振方向沿两个双折射轴的分量强度相等时,在同为反常色散区和正常色散区所产生的调制不稳定性.结果表明在反常色散区和正常色散区都能产生调制不稳定性;在正常色散区存在不同的调制不稳定性功率区域,对应不同的功率区域,导致增益谱表现出明显的不同,并且当输入功率一定时,波长差(或频率差)的变化导致增益谱的变化.
关键词:
相近频率传输区域
双折射
保偏光纤
调制不稳定性 相似文献
110.
A. D. Myshkis 《Mathematical Notes》2006,79(1-2):92-96
We consider a finite heat conducting medium whose boundary is maintained at zero temperature and, moreover, to which the same amount of heat is supplied at a certain point at the instant when the temperature at this point decreases to a given level. Up to an arbitrary shift in time, we prove the existence and uniqueness of a periodic regime with a unique heat pulse during each period. We present an efficient algorithm for constructing this regime if the medium is either an n-dimensional ball heated at the center or an interval heated at an arbitrary point. 相似文献