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1.
Odd Viscosity     
When time reversal is broken, the viscosity tensor can have a nonvanishing odd part. In two dimensions, and only then, such odd viscosity is compatible with isotropy. Elementary and basic features of odd viscosity are examined by considering solutions of the wave and Navier–Stokes equations for hypothetical fluids where the stress is dominated by odd viscosity.  相似文献   

2.
The systems exhibiting sustainable external energy exchange are abundant, e.g., biological organisms' reaction to external stimuli while maintaining a constant energy exchange with the surrounding. In a linear mechanical system exhibiting an external energy gain or release, the recently proposed odd elasticity theory can characterize the overall stress and strain response.However, realizing the required odd elasticity is still challenging. In this work, we discovered that the smart materials with designed feedbacks can achieve this odd elasticity, thereby providing a practical platform to analyze the phenomenon related to this novel elasticity theory. We also demonstrated this idea by designing a non-reciprocal Rayleigh wave via odd elasticity and the equivalent piezoelectricity with linear feedback. The underpinned electric energy scenario was also examined. Our work establishes a method to easily realize the materials with odd elastic behaviors and explore the rich phenomena related to nonHermitian systems.  相似文献   

3.
We generalize the superfield method of Dirac quantization to the odd sector of superspace for N = 2 extended models. We discuss the mechanism of generating constraints in the odd sector of supersymmetric classical mechanics and then Dirac quantization in the odd superspace in superfield version. An example of supersymmetric system, defined by odd superfields, and the application of the method in the odd superspace is given.  相似文献   

4.
We consider odd Laplace operators acting on densities of various weights on an odd Poisson (= Schouten) manifold M. We prove that the case of densities of weight 1/2 (half-densities) is distinguished by the existence of a unique odd Laplace operator depending only on a point of an 'orbit space' of volume forms. This includes earlier results for the odd symplectic case, where there is a canonical odd Laplacian on half-densities. The space of volume forms on M is partitioned into orbits by the action of a natural groupoid whose arrows correspond to the solutions of the quantum Batalin–Vilkovisky equations. We compare this situation with that of Riemannian and even Poisson manifolds. In particular, we show that the square of an odd Laplace operator is a Poisson vector field defining an analog of Weinstein's 'modular class'.  相似文献   

5.
Wu  F. Y.  Kunz  H. 《Journal of statistical physics》2004,116(1-4):67-78
We consider a vertex model on the simple-quartic lattice defined by line graphs on the lattice for which there is always an odd number of lines incident at a vertex. This is the odd 8-vertex model which has eight possible vertex configurations. We establish that the odd 8-vertex model is equivalent to a staggered8-vertex model. Using this equivalence we deduce the solution of the odd8-vertex model when the weights satisfy a free-fermion condition. It is found that the free-fermion model exhibits no phase transitions in the regime of positive vertex weights. We also establish the complete equivalence of the free-fermion odd 8-vertex model with the free-fermion 8-vertex model solved by Fan and Wu. Our analysis leads to several Ising model representations of thefree-fermion model with pure 2-spin interactions.  相似文献   

6.
J Tan  M Lu  A Stein  W Jiang 《Optics letters》2012,37(15):3189-3191
We demonstrate a novel scheme to control the excitation symmetry for an odd mode in a photonic crystal waveguide and investigate the spectral signature of this slow light mode. An odd-mode Mach-Zehnder coupler is introduced to transform mode symmetry and excite a high-purity odd mode with 20?dB signal contrast over the background. Assisted by a mixed-mode Mach-Zehnder coupler, slow light mode beating can be observed and is utilized to determine the group index of this odd mode. With slow light enhancement, this odd mode can help enable novel miniaturized devices such as one-way waveguides.  相似文献   

7.
偶奇qs相干态的非经典特性   总被引:7,自引:1,他引:6  
王继锁  赵铭健 《光学学报》1997,17(3):93-297
利用数值计算方法研究了q和s畸变对双参数形变偶奇qs相干态量子统计特性的委现偶奇qs相干态与通常的偶奇相干态有着显著不同的量子统计性质,压缩效应和反聚束效应均可在一定条件下的两种双参数畸变态中出现,偶奇qs相干态和通常偶奇相干态的差异随q值偏离1越大和s的取值越小而越大。  相似文献   

8.
PropertiesofAmplitudeNth┐powerSqueezingofEvenandOddqs┐CoherentStatesWANGJisuo1)SUNChangyong1)HEJinyu2)(1)DepartmentofPhysics...  相似文献   

9.
偶奇相干态的q-类比   总被引:10,自引:4,他引:6  
匡乐满  王发伯  曾高坚 《光学学报》1993,13(11):008-1011
在偶奇相干态的基础上,构造出偶、奇q-相干态,并讨论了它们的光统计特性.计算分析表明:偶奇q-相干态的光统计特性,是完全不相同的.  相似文献   

10.
增、减光子奇偶相干态的Wigner函数   总被引:6,自引:0,他引:6       下载免费PDF全文
利用Fock态表象下的Wigner函数定义,重构了增、减光子奇偶相干态的Wigner函数,并据此 讨论了它们的非经典性质.结果表明:增光子奇偶相干态总呈现出非经典特征,而减光子奇 偶相干态分别仅在k为偶数和奇数时呈现出非经典特征. 关键词: 奇偶相干态 玻色算符的逆算符 Wigner函数  相似文献   

11.
In this paper, we use the numerical method to study the influences of q and s deformations on the quantum statistical Properties of even and odd qs-coherent states. It is shown that nonclassical properties of the even and odd qs-coherent states are very different from those of the usual even and odd coherent states. It is found that squeezing and antibunching effect appear for both even and odd qs-coherent states in some range of the parameters q, s and r. The smaller the q (q < 1) and s are, the.Jarger the difference between the even and odd qs-coherent states and the usual even and odd coherent states is.  相似文献   

12.
压缩奇偶相干态的量子统计性质   总被引:8,自引:2,他引:6  
路洪  郭光灿 《光子学报》1998,27(12):1074-1077
用压缩算子作用在奇偶相干态上即可得到压缩奇偶相干态.本文研究了这类量子态的统计特性.结果表明,压缩奇相干态和压缩偶相干态都能处于压缩状态,它们的光子亦都可能出现反聚束的现象.  相似文献   

13.
The symmetry property of the transition matrix for a reaction producing an isobaric multiplet (or identical particles) is derived from the generalized Pauli principle without any specific assumptions concerning the reaction mechanism. In contrast to previous predictions it is shown that for odd partial waves in the exit channel the cross section will generally not vanish at Θ = π/2 if the channel spin projections of the initial and final channels may be different.  相似文献   

14.
We introduce a new canonical trace on odd class logarithmic pseudo-differential operators on an odd dimensional manifold, which vanishes on commutators. When restricted to the algebra of odd class classical pseudo-differential operators our trace coincides with the canonical trace of Kontsevich and Vishik. Using the new trace we construct a new determinant of odd class classical elliptic pseudo-differential operators. This determinant is multiplicative up to sign whenever the multiplicative anomaly formula for usual determinants of Kontsevich–Vishik and Okikiolu holds. When restricted to operators of Dirac type our determinant provides a sign refined version of the determinant constructed by Kontsevich and Vishik. We discuss some applications of the symmetrized determinant to a non-linear sigma-model in superconductivity.  相似文献   

15.
Roy-型奇偶非线性相干态的位相概率分布   总被引:4,自引:0,他引:4       下载免费PDF全文
王继锁  刘堂昆  冯健  孙金祚 《物理学报》2004,53(11):3729-3732
借助于数值计算方法,研究了Roy-型奇偶非线性相干态的位相概率分布特性.结果表明,它们的位相概率分布不同;与通常的奇偶相干态不同,在这种新的奇偶非线性相干态中,Pegg-Barnett位相概率分布能明显地反映出不同的量子干涉特性. 关键词: Roy-型奇偶非线性相干态 Pegg-Barnett位相算符公式 位相概率分布  相似文献   

16.
Using the coherent state representation of Wigner operator and the technique of integration within an ordered product (IWOP) of operators, the Wigner functions of the even and odd negative binomial states (NBSs) are obtained. We concentrate our analysis on the fact that the even and odd NBSs interpolate between the even and odd coherent states and the even and odd quasi-thermal states depending on the values of the parameters involved. Moreover, the tomograms of the even and odd NBSs are calculated by virtue of intermediate coordinate-momentum representation in quantum optics. Project 10574060 supported by the National Natural Science Foundation of China and project Q2007A01 supported by the Natural Science Foundation of Shandong Province.  相似文献   

17.
于舸  于肇贤 《光子学报》1995,24(5):385-387
研究结果表明,只有当以k>3)为奇数时,偶q相干态呈现振幅k次方压缩性质;无论k为偶数还是奇数,奇q相干态均不呈现压缩性质。  相似文献   

18.
借助于Pegg-Barnett相位算符理论和数值计算方法,研究了增光子奇偶相干态的相位概率分布,在此基础之上,讨论了有关数算符和相位算符的压缩特性。结果表明,增光子奇偶相干态的相位概率分布与通常的奇偶相干态、非线性相干态不同,在这种新的奇偶相干态中,其Pegg-Barnett相位概率分布能明显地反映出不同的量子相位信息和干涉特性。同时发现,在参量α的某些不同的取值范围内,增光子奇偶相干态在数算符和相位算符分量上均存在压缩效应。  相似文献   

19.
Kerr偶奇相干态及其非经典性   总被引:6,自引:0,他引:6  
詹佑邦  朱小芹 《光子学报》1998,27(3):215-219
本文对Ker偶奇相干态及其非经典性质进行了研究。结果表明:Kerr偶相干态可呈现周期性的二阶压缩效应,Kerr奇相干态则不存在这种压缩效应;但两者均可呈现周期性的振幅平方压缩效应,这与通常偶奇相干态的情形有所不同。  相似文献   

20.
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