English
Related papers

Related papers: Average capacity of quantum entanglement

200 papers

Given a unitary operator $U$ acting on a composite quantum system what is the entangling capacity of $U$? This question is investigated using a geometric approach. The entangling capacity, defined via metrics on the unitary groups, leads to…

Quantum Physics · Physics 2023-06-13 Manas K Patra

Quantum Neural Networks (QNN) are considered a candidate for achieving quantum advantage in the Noisy Intermediate Scale Quantum computer (NISQ) era. Several QNN architectures have been proposed and successfully tested on benchmark datasets…

We investigate entanglement production in a class of quantum baker's maps. The dynamics of these maps is constructed using strings of qubits, providing a natural tensor-product structure for application of various entanglement measures. We…

Quantum Physics · Physics 2007-05-23 A. J. Scott , Carlton M. Caves

We show that universal quantum computation can be achieved in the standard pure-state circuit model while, at any time, the entanglement entropy of all bipartitions is small---even tending to zero with growing system size. The result is…

Quantum Physics · Physics 2013-04-11 Maarten Van den Nest

We present a study of the entanglement properties of Gaussian cluster states, proposed as a universal resource for continuous-variable quantum computing. A central aim is to compare mathematically-idealized cluster states defined using…

Quantum Physics · Physics 2010-11-30 Hugo Cable , Daniel E. Browne

The quantum nature of bulk ensemble NMR quantum computing --the center of recent heated debate, is addressed. Concepts of the mixed state and entanglement are examined, and the data in a 2 qubit liquid NMR quantum computation are analyzed.…

Quantum Physics · Physics 2007-05-23 G L Long , H Y Yan , Y s Li , C C Tu , s J Zhu , D Ruan , Y Sun , J X Tao , H M Chen

A measure of entanglement production by quantum operations is suggested. This measure is general, being valid for operations over pure states as well as over mixed states, for equilibrium as well as for nonequilibrium processes. The measure…

Quantum Physics · Physics 2025-08-01 V. I. Yukalov , E. P. Yukalova

Structure in quantum entanglement entropy is often leveraged to focus on a small corner of the exponentially large Hilbert space and efficiently parameterize the problem of finding ground states. A typical example is the use of matrix…

Statistical Mechanics · Physics 2023-04-17 Bart Olsthoorn

The expected indefinite causal structure in quantum gravity poses a challenge to the notion of entanglement: If two parties are in an indefinite causal relation of being spacelike and timelike, can they still be entangled? If so, how does…

Quantum Physics · Physics 2018-02-27 Ding Jia

The entangling power of a unitary operator quantifies its ability to generate entanglement from product states and provides a natural probe of quantum many-body dynamics. Entanglement extremization at points of enhanced symmetry has…

Quantum Physics · Physics 2026-05-21 Ian Low , Pallab Goswami

What can we learn about entanglement between individual particles in macroscopic samples by observing only the collective properties of the ensembles? Using only a few experimentally feasible collective properties, we establish an…

Quantum Physics · Physics 2007-05-23 Johannes Kofler , Caslav Brukner

We review studies of entanglement entropy in systems with quenched randomness, concentrating on universal behavior at strongly random quantum critical points. The disorder-averaged entanglement entropy provides insight into the quantum…

Disordered Systems and Neural Networks · Physics 2015-05-13 Gil Refael , Joel E. Moore

Quantum many-body systems display an extraordinary degree of complexity, yet many of their features are universal: they depend not on microscopic details, but on a few fundamental physical aspects such as symmetries. A central challenge is…

Quantum Physics · Physics 2026-02-02 Jia-Nan Yang , Lata Kh Joshi , Filiberto Ares , Yihang Han , Pengfei Zhang , Pasquale Calabrese

We investigate entanglement properties of a recently introduced class of macroscopic quantum superpositions in two-mode mixed states. One of the tools we use in order to infer the entanglement in this non-Gaussian class of states is the…

Quantum Physics · Physics 2009-11-11 M. Paternostro , H. Jeong , M. S. Kim

Entanglement properties of bipartite unitary operators are studied via their local invariants, namely the entangling power $e_p$ and a complementary quantity, the gate typicality $g_t$. We characterize the boundaries of the set $K_2$…

Quantum Physics · Physics 2020-10-28 Bhargavi Jonnadula , Prabha Mandayam , Karol Życzkowski , Arul Lakshminarayan

Entanglement is a physical resource of a quantum system just like mass, charge or energy. Moreover it is an essential tool for many purposes of nowadays quantum information processing, e.g. quantum teleportation, quantum cryptography or…

Disordered Systems and Neural Networks · Physics 2008-02-15 Imre Varga , Jose Antonio Mendez-Bermudez

The entanglement spectrum, i.e., the full distribution of Schmidt eigenvalues of the reduced density matrix, contains more information than the conventional entanglement entropy and has been studied recently in several many-particle…

Strongly Correlated Electrons · Physics 2011-02-02 Maurizio Fagotti , Pasquale Calabrese , Joel E. Moore

We study the statistical behavior of entanglement in quantum bipartite systems over fermionic Gaussian states as measured by von Neumann entropy and entanglement capacity. The focus is on the variance of von Neumann entropy and the mean…

Mathematical Physics · Physics 2022-02-16 Youyi Huang , Lu Wei

Studying the typical entanglement entropy of a bipartite system when averaging over different ensembles of pure quantum states has been instrumental in different areas of physics, ranging from many-body quantum chaos to black hole…

Quantum Physics · Physics 2025-07-08 Lucas Hackl , Mario Kieburg , Joel Maldonado

We derive an explicit analytic estimate for the entanglement of a large class of bipartite quantum states which extends into bound entanglement regions. This is done by using an efficiently computable concurrence lower bound, which is…