Institute for Quantum Information Science and Department of Mathematics and Statistics, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4.
Phys Rev Lett. 2013 Aug 9;111(6):060502. doi: 10.1103/PhysRevLett.111.060502. Epub 2013 Aug 8.
We provide a systematic classification of multiparticle entanglement in terms of equivalence classes of states under stochastic local operations and classical communication (SLOCC). We show that such a SLOCC equivalency class of states is characterized by ratios of homogenous polynomials that are invariant under local action of the special linear group. We then construct the complete set of all such SL-invariant polynomials (SLIPs). Our construction is based on Schur-Weyl duality and applies to any number of qudits in all (finite) dimensions. In addition, we provide an elegant formula for the dimension of the homogenous SLIPs space of a fixed degree as a function of the number of qudits. The expressions for the SLIPs involve in general many terms, but for the case of qubits we also provide much simpler expressions.
我们提供了一种基于随机局部操作和经典通信(SLOCC)下的状态等价类的多粒子纠缠的系统分类。我们表明,这样的 SLOCC 等价类状态的特征是齐次多项式的比值,这些比值在特殊线性群的局部作用下是不变的。然后,我们构造了所有这样的 SL 不变多项式(SLIP)的完整集合。我们的构造基于舒尔-魏尔对偶性,并适用于所有(有限)维度中任意数量的量子位。此外,我们还提供了一个优雅的公式,用于计算固定度数的齐次 SLIP 空间的维数作为量子位数的函数。SLIP 的表达式通常涉及很多项,但对于量子比特的情况,我们也提供了更简单的表达式。