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Related papers: Geometric measure for two-qubit CS-states: an exac…

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We study the Hilbert-Schmidt measure on the manifold of mixed Gaussian states in multi mode continuous variable quantum systems. An analytical expression for the Hilbert-Schmidt volume element is derived. Its corresponding probability…

Quantum Physics · Physics 2015-03-10 Valentin Link , Walter T. Strunz

We formulate the conditions under which the dynamics of a continuously measured quantum system becomes indistinguishable from that of the corresponding classical system. In particular, we demonstrate that even in a classically chaotic…

Quantum Physics · Physics 2009-01-23 Tanmoy Bhattacharya , Salman Habib , Kurt Jacobs

We define a multiparty entanglement measure, called generalized geometric measure, that can detect and quantify genuine multiparty entanglement for any number of parties. The quantum phase transitions in exactly solvable models like the…

Quantum Physics · Physics 2010-02-08 Aditi Sen De , Ujjwal Sen

We introduce a measure of average dimensionality (or coherence) for high-dimensional quantum devices. This includes sets of quantum measurements, steering assemblages, and quantum channels. For measurements and channels, our measure…

Quantum Physics · Physics 2023-06-22 Thomas Cope , Roope Uola

Based on the residual entanglement [9] (Phys. Rev. A \textbf{71}, 044301 (2005)), we present the global entanglement for a multipartite quantum state. The measure is shown to be also obtained by the bipartite partitions of the multipartite…

Quantum Physics · Physics 2009-11-13 Chang-shui Yu , He-shan Song

Entangled measurement is a crucial tool in quantum technology. We propose a new entanglement measure of multi-mode detection, which estimates the amount of entanglement that can be created in a measurement. To illustrate the proposed…

The geometric measure of entanglement (GME) quantifies how close a multi-partite quantum state is to the set of separable states under the Hilbert-Schmidt inner product. The GME can be non-multiplicative, meaning that the closest product…

Quantum Physics · Physics 2025-07-24 Daniel Dilley , Jerry Chang , Jeffrey Larson , Eric Chitambar

We extend the Hilbert-Schmidt (square norm) distance, previously used to define the geometric quantum discord, to define also geometric quantifiers of total and classical correlations. We then compare the dynamics of geometric and entropic…

Quantum Physics · Physics 2012-07-19 Bruno Bellomo , Rosario Lo Franco , Giuseppe Compagno

We give a simple formula for finding the spectral norm of d-mode symmetric tensor in two variables over the complex or real numbers in terms of the complex or real roots of a corresponding polynomial in one complex variable. This result…

Rings and Algebras · Mathematics 2017-03-07 Shmuel Friedland , Li Wang

The entanglement criterion for continuous variable systems and the conditions under which the uncertainty relations are fulfilled are generalized to the case of a noncommutative (NC) phase-space. The quantum nature and the separability of…

A promising practical application of entanglement is metrology, where quantum states can be used to make measurements beyond the shot noise limit. Here we consider how metrology schemes could be realised using atomic Bose-Einstein…

Quantum Physics · Physics 2015-05-27 J. A. Dunningham , J. J. Cooper , D. W. Hallwood

In this paper, we study the geometric phase (GP) of two-mode entangled squeezed-coherent states (ESCSs), undergoing a unitary cyclic evolution. It is revealed that by increasing the squeezing parameter of the first or the second mode of a…

Quantum Physics · Physics 2023-04-18 Sanaz Mohammadi Almas , Ghader Najarbashi , Ali Tavana

Asymmetry of quantum states is a useful resource in applications such as quantum metrology, quantum communication, and reference frame alignment. However, asymmetry of a state tends to be degraded in physical scenarios where…

Quantum Physics · Physics 2017-02-23 Da-Jian Zhang , Xiao-Dong Yu , Hua-Lin Huang , D. M. Tong

We propose a new criterion to judge zero quantum discord for arbitrary bipartite states. A bipartite quantum state has zero quantum discord if and only if all blocks of its density matrix are normal matrices and commute with each other.…

Quantum Physics · Physics 2015-03-19 Jie-Hui Huang , Lei Wang , Shi-Yao Zhu

The relation between quantum phase transitions, entanglement, and geometric phases is investigated with a system of two qubits with XY type interaction. A seam of level crossings of the system is a circle in parameter space of the…

Quantum Physics · Physics 2009-10-31 Sangchul Oh

In a previous paper we examined a geometric measure of entanglement based on the minimum distance between the entangled target state of interest and the space of unnormalized product states. Here we present a detailed study of this…

Quantum Physics · Physics 2015-05-27 D. Buhr , M. E. Carrington , T. Fugleberg , R. Kobes , G. Kunstatter , D. McGillis , C. Pugh , D. Ryckman

We show that the geometry of the set of quantum states plays a crucial role in the behavior of entanglement in different physical systems. More specifically it is shown that singular points at the border of the set of unentangled states…

We quantify the geometric measure of entanglement in terms of mean values of observables of entangled system. For pure states we find the relation of geometric measure of entanglement with the mean value of spin one-half for the system…

Quantum Physics · Physics 2017-10-11 A. M. Frydryszak , M. I. Samar , V. M. Tkachuk

We discuss the uniqueness of quantum states compatible with given results for measuring a set of observables. For a given pure state, we consider two different types of uniqueness: (1) no other pure state is compatible with the same…

We prove that the binegativity is always positive for any two-qubit state. As a result, as suggested by the previous works, the asymptotic relative entropy of entanglement in two qubits does not exceed the Rains bound, and the…

Quantum Physics · Physics 2007-05-23 Satoshi Ishizaka