English
Related papers

Related papers: Local Unitary Invariants of Generic Multi-qubit St…

200 papers

We study the local unitary equivalence for two and three-qubit mixed states by investigating the invariants under local unitary transformations. For two-qubit system, we prove that the determination of the local unitary equivalence of…

Quantum Physics · Physics 2017-07-14 Bao-zhi Sun , Shao-Ming Fei , Zhi-xi Wang

We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations is presented for a class of non-generic three-qubit mixed states. It is shown that two…

Quantum Physics · Physics 2015-06-26 Bao-Zhi Sun , Shao-Ming Fei

We investigate means to describe the non-local properties of quantum systems and to test if two quantum systems are locally equivalent. For this we consider quantum systems that consist of several subsystems, especially multiple qubits. We…

Quantum Physics · Physics 2023-11-27 Markus Grassl , Martin Roetteler , Thomas Beth

Local unitary equivalence is an important ingredient for quantifying and classifying entanglement. Verifying whether or not two quantum states are local unitary equivalent is a crucial problem, where only the case of multipartite pure…

Quantum Physics · Physics 2024-02-27 Qing Zhou , Yi-Zheng Zhen , Xin-Yu Xu , Shuai Zhao , Wen-Li Yang , Shao-Ming Fei , Li Li , Nai-Le Liu , Kai Chen

In the present paper few steps are undertaken towards the description of the qubit-qutrit pair - quantum bipartite system composed of two and three level subsystems. The computational difficulties with the construction of the local unitary…

Quantum Physics · Physics 2012-06-21 Vladimir Gerdt , Arsen Khvedelidze , Dimitar Mladenov , Yuri Palii

Given L-qubit states with the fixed spectra of reduced one-qubit density matrices, we find a formula for the minimal number of invariant polynomials needed for solving local unitary (LU) equivalence problem, that is, problem of deciding if…

Quantum Physics · Physics 2014-07-18 Tomasz Maciazek , Michał Oszmaniec , Adam Sawicki

Research on quantum states often focuses on the correlation between nonlocal effects and local unitary invariants, among which local unitary equivalence plays a significant role in quantum state classification and resource theories. This…

Quantum Physics · Physics 2025-11-17 Lin Zhang , Bing Xie , Yuanhong Tao

We study the equivalence of mixed states under local unitary transformations. First we express quantum states in Bloch representation. Then based on the coefficient matrices, some invariants are constructed. This method and results can be…

Quantum Physics · Physics 2020-03-25 Meiyu Cui , Jingmei Chang , Ming-Jing Zhao , Xiaofen Huang , Tinggui Zhang

We study the invariants of arbitrary dimensional multipartite quantum states under local unitary transformations. For multipartite pure states, we give a set of invariants in terms of singular values of coefficient matrices. For…

Quantum Physics · Physics 2015-09-04 Ting-Gui Zhang , Ming-Jing Zhao , Xianqing Li-Jost , Shao-Ming Fei

We present an approach of constructing invariants under local unitary transformations for multipartite quantum systems. The invariants constructed in this way can be complement to that in [Science 340 (2013) 1205-1208]. Detailed examples…

Quantum Physics · Physics 2015-06-23 Jing Wang , Ming Li , Shao-Ming Fei , Xianqing Li-Jost

We present computable criterion for completely classifying multi-qubit quantum states under local unitary operations. The criterion can be used to detect whether two quantum states in multi-qubit systems are local unitary equivalent or not.…

Quantum Physics · Physics 2014-06-25 Ming Li , Tinggui Zhang , Shao-Ming Fei , Xianqing Li-Jost , Naihuan Jing

We give an algorithm allowing to construct bases of local unitary invariants of pure k-qubit states from the knowledge of polynomial covariants of the group of invertible local filtering operations. The simplest invariants obtained in this…

Quantum Physics · Physics 2013-02-12 Frederic Toumazet , Jean-Gabriel Luque , Jean-Yves Thibon

We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations is presented for a class of mixed states. It is shown that two states in this class are…

Quantum Physics · Physics 2009-11-11 Sergio Albeverio , Shao-Ming Fei , Debashish Goswami

The nonlocal properties of arbitrary dimensional bipartite quantum systems are investigated. A complete set of invariants under local unitary transformations is presented. These invariants give rise to both sufficient and necessary…

Quantum Physics · Physics 2012-07-12 Chunqin Zhou , Tinggui Zhang , Shao-Ming Fei , Naihuan Jing , Xianqing Li-Jost

We calculate the field of rational local unitary invariants for mixed states of two qubits, by employing methods from algebraic geometry. We prove that this field is rational (i.e. purely transcendental), and that it is generated by nine…

Quantum Physics · Physics 2023-05-26 Luca Candelori , Vladimir Y. Chernyak , John R. Klein , Nick Rekuski

Entanglement of two parts of a quantum system is a non-local property unaffected by local manipulations of these parts. It is described by quantities invariant under local unitary transformations. Here we present, for a system of two…

Quantum Physics · Physics 2007-05-23 Yuriy Makhlin

We study invariants of three-qubit states under local unitary transformations, i.e. functions on the space of entanglement types, which is known to have dimension 6. We show that there is no set of six independent polynomial invariants of…

Quantum Physics · Physics 2009-11-06 Anthony Sudbery

We compute the field of rational local unitary invariants for locally maximally mixed states and symmetrically mixed states of two qubits. In both cases, we prove that the field of rational invariants is purely transcendental. We also…

Algebraic Geometry · Mathematics 2023-08-09 Luca Candelori , Vladimir Y. Chernyak , John R. Klein , Nick Rekuski

We present two general methods to implement quantum circuits for the direct measuring of local unitary invariants on quantum computers. We work these out for important three-qubit invariants, and also demonstrate these on the IBM Quantum…

Quantum Physics · Physics 2026-04-20 Szilárd Szalay , Frédéric Holweck

We study the equivalence of quantum states under local unitary transformations by using the singular value decomposition. A complete set of invariants under local unitary transformations is presented for several classes of tripartite mixed…

Quantum Physics · Physics 2009-11-13 Xiao-Hong Wang , Shao-Ming Fei , Ke Wu
‹ Prev 1 2 3 10 Next ›