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Related papers: The Complexity of Being Entangled

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Quantum entanglement is an enigmatic and powerful property that has attracted much attention due to its usefulness in new ways of communications, like quantum teleportation and quantum key distribution. Much effort has been done to quantify…

Quantum Physics · Physics 2007-06-29 Joao Luzeilton de Oliveira , Rubens Viana Ramos

Entanglement detection in high dimensional systems is a NP-hard problem since it is lacking an efficient way. Given a bipartite quantum state of interest free entanglement can be detected efficiently by the PPT-criterion (Peres-Horodecki…

Quantum Physics · Physics 2021-10-07 Beatrix C. Hiesmayr

Entanglement is a unique nature of quantum theory and has tremendous potential for application. Nevertheless, the complexity of quantum entanglement grows exponentially with an increase in the number of entangled particles. Here we…

Quantum Physics · Physics 2018-01-17 S. M. Zangi , Jun-Li Li , Cong-Feng Qiao

This topical review article reports rapid progress on the generalization and application of entanglement in non-Hermitian free-fermion quantum systems. We begin by examining the realization of non-Hermitian quantum systems through the…

Quantum Physics · Physics 2026-01-14 Li-Mei Chen , Yao Zhou , Shuai A. Chen , Peng Ye

Quantum mechanics exhibits a wide range of nonclassical features, of which entanglement in multipartite systems takes a central place. In several specific settings, it is well known that nonclassicality (e.g., squeezing, spin squeezing,…

Quantum Physics · Physics 2016-02-25 Nathan Killoran , Frank E. S. Steinhoff , Martin B. Plenio

The entanglement production in bipartite quantum systems is studied for initially unentangled product eigenstates of the subsystems, which are assumed to be quantum chaotic. Based on a perturbative computation of the Schmidt eigenvalues of…

Squashed entanglement is a measure for the entanglement of bipartite quantum states. In this paper we present a lower bound for squashed entanglement in terms of a distance to the set of separable states. This implies that squashed…

Quantum Physics · Physics 2012-07-23 Fernando G. S. L. Brandao , Matthias Christandl , Jon Yard

Quantifying quantum entanglement is a pivotal challenge in quantum information science, particularly for high-dimensional systems, due to its computational complexity. This thesis extends the geometric measure of entanglement (GME) to…

Quantum Physics · Physics 2025-06-16 Xuanran Zhu

We analyze the properties of entangled random pure states of a quantum system partitioned into two smaller subsystems of dimensions $N$ and $M$. Framing the problem in terms of random matrices with a fixed-trace constraint, we establish,…

Statistical Mechanics · Physics 2016-05-11 Pierpaolo Vivo , Mauricio P. Pato , Gleb Oshanin

In quantum computation every unitary operation can be decomposed into quantum circuits-a series of single-qubit rotations and a single type entangling two-qubit gates, such as controlled-NOT (CNOT) gates. Two measures are important when…

Quantum Physics · Physics 2011-03-07 Martin Plesch , Časlav Brukner

We advance holographic constructions for the entanglement negativity of bipartite states in a class of $(1+1)-$dimensional Galilean conformal field theories dual to asymptotically flat three dimensional bulk geometries described by Einstein…

High Energy Physics - Theory · Physics 2022-03-10 Debarshi Basu , Ashish Chandra , Himanshu Parihar , Gautam Sengupta

We study Nielsen complexity and Fubini-Study complexity for a class of exactly solvable one dimensional spin systems. Our examples include the transverse XY spin chain and its natural extensions, the quantum compass model with and without…

Statistical Mechanics · Physics 2021-08-25 Nitesh Jaiswal , Mamta Gautam , Tapobrata Sarkar

Quantifying the entanglement generation of a multipartite unitary operation is a key problem in quantum information processing. We introduce the definition of multipartite entangling, assisted entangling, and disentangling power, which is a…

Quantum Physics · Physics 2024-10-22 Xinyu Qiu , Zhiwei Song , Lin Chen

We present a family of correlations constraints that apply to all multipartite quantum systems of finite dimension. The size of this family is exponential in the number of subsystems. We obtain these relations by defining and investigating…

Quantum Physics · Physics 2018-11-21 Christopher Eltschka , Felix Huber , Otfried Gühne , Jens Siewert

Entanglement of pure states of bipartite quantum systems has been shown to have a unique measure in terms of the von Neumann entropy of the reduced states of either of its subsystems. The measure is established under entanglement…

Quantum Physics · Physics 2007-05-23 Garry Bowen , Nilanjana Datta

We develop a unified quantum framework for subgraph counting in graphs. We encode a graph on $N$ vertices into a quantum state on $2\lceil \log_2 N \rceil$ working qubits and $2$ ancilla qubits using its adjacency list, with worst-case gate…

Quantum Physics · Physics 2026-04-22 Bibhas Adhikari

Characterizing the entanglement structure of ground states of local Hamiltonians is a fundamental problem in quantum information. In this work we study the computational complexity of this problem, given the Hamiltonian as input. Our main…

Quantum Physics · Physics 2024-11-08 Adam Bouland , Chenyi Zhang , Zixin Zhou

Entanglement is a striking feature of quantum mechanics, and it has a key property called unextendibility. In this paper, we present a framework for quantifying and investigating the unextendibility of general bipartite quantum states.…

Quantum Physics · Physics 2024-03-28 Kun Wang , Xin Wang , Mark M. Wilde

We search a simplest and minimal way to determine whether a given quantum system is entangled or separable. For this end, we propose binary correlation measurements in which restricted knowledge of only zero or non-zero correlations is…

Quantum Physics · Physics 2021-06-29 Toru Ohira

We present a new technique to reduce the expected number of measurements to declare an unknown quantum state as entangled. Our method is based on the geometric criterion and so requires only local Pauli measurements. Using concentration of…

Quantum Physics · Physics 2017-09-13 Bingjie Wang , Stephen Brierley