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111.
112.
Sutapa Saha Some Sankar Bhattacharya Tamal Guha Saronath Halder Manik Banik 《Annalen der Physik》2020,532(12):2000334
Quantum correlations provide dramatic advantage over the corresponding classical resources in several communication tasks. However, a broad class of probabilistic theories exists that attributes greater success than quantum theory in many of these tasks by allowing supra-quantum correlations in “space-like” and/or “time-like” paradigms. In this letter, a communication task involving three spatially separated parties is proposed where one party (verifier) aims to verify whether the bit strings possessed by the other two parties (terminals) are equal or not. This task is called authentication with limited communication, the restrictions on communication being: i) the terminals cannot communicate with each other, but (ii) each of them can communicate with the verifier through single use of channels with limited capacity. Manifestly, classical resources are not sufficient for perfect success of this task. Moreover, it is also not possible to perform this task with certainty in several nonclassical theories although they might possess stronger “space-like” and/or “time-like” correlations. Surprisingly, quantum resources can achieve the perfect winning strategy. The proposed task thus stands apart from all previously known communication tasks as it exhibits quantum advantage over other nonclassical strategies. 相似文献
113.
ZHAO Ren ZHANG Li-Chun HU Shuang-Qi 《理论物理通讯》2006,46(4):635-638
We generalize the method that is used to study corrections to Cardy-Verlinde formula due to generalized uncertainty principle and discuss corrections to Cardy-Verlinde formula due to generalized uncertainty principle in (anti)- de Sitter space. Because in de Sitter black hole spacetime the radiation temperature of the black hole horizon is different from the one of the cosmological horizon, this spacetime is a thermodynamical non-equilibrium spacetime. 相似文献
114.
Three-dimensional systems possessing a homoclinic orbit associated to a saddle focus with eigenvalues ±i, – and giving rise to homoclinic chaos when the Shil'nikov condition < is satisfied are studied. The 2D Poincaré map and its 1D contractions capturing the essential features of the flow are given. At homoclinicity, these 1D maps are found to be piecewise linear. This property allows one to reduce the Frobenius—Perron equation to a master equation whose solution is analytically known. The probabilistic properties such as the time autocorrelation function of the state variablex are explicitly derived. 相似文献
115.
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117.
The concept of partially coherent nonparaxial modified Bessel--Gauss (MBG)
beams is proposed. Based on the generalized Rayleigh-Sommerfeld diffraction
integral, the analytical propagation equations of nonparaxial MBG beams in
free space are derived and analysed, and some special cases are discussed.
In particular, under the paraxial approximation our results reduce to the
corresponding paraxial ones. Numerical calculation examples are given to
illustrate the dependence of intensity and spectral degree of coherence on
the beam order $m$, \textit{$\xi $} and $f$ parameters, and to compare
the difference between the paraxial and nonparaxial results. 相似文献
118.
Quantum circuits for realizing deterministic and exact teleportation via two partially entangled pairs of particles 下载免费PDF全文
Deterministic and exact teleportation can be achieved via two partially
entangled pairs of particles [Gu Y J 2006 {\em Opt. Comm.} {\bf 259} 385]. The key point of the protocol is a generalized measurement described by a positive operator-valued measure, which can be realized by performing a unitary operation in the extended space and a conventional Von Neumann orthogonal measurement. By decomposing the evolution process from the initial state to the final state, we construct the quantum circuits for realizing the unitary operation with quantum Toffoli gates, and thus provide a physical means to realize the teleportation. Our method for constructing quantum circuits differs from the usual methods based on decomposition of unitary matrices, and is convenient for a large class of quantum processes involving generalized measurements. 相似文献
119.
A conclusive teleportation protocol of a d-dimensional two-particle unknown quantum state using three d- dimensional particles in an arbitrary pure state is proposed. A sender teleports the unknown state conclusively to a receiver by using the positive operator valued measure(POVM) and introducing an ancillary qudit to perform the generalized Bell basis measurement, We calculate the optimal teleportation fidelity. We also discuss and analyse the reason why the information on the teleported state is lost in the course of the protocol, 相似文献
120.
应用多尺度微扰理论到广义非简谐振子, 得到了一阶经典和量子微扰解. 特别是
我们的量子解在极限条件下能方便地转变为经典解, 并且坐标和动量算符的对易
关系的简化十分自然. 与Taylor级数解相比较, 无论是在经典还是在量子解
中频率移动都出现在各阶振动表达式中, 所以多尺度微扰解是弱耦合非简谐振动的较好解法. 相似文献