scholarly journals On the upper bound of classical correlations in a bipartite quantum system

2017 ◽  
Vol 50 (41) ◽  
pp. 415301
Author(s):  
Theresa Christ ◽  
Haye Hinrichsen
Keyword(s):  
Quantum System ◽  
Upper Bound ◽  
Bipartite Quantum System ◽  
Classical Correlations

scholarly journals Extracting classical correlations from a bipartite quantum system

2003 ◽  
Vol 67 (1) ◽  
Author(s):  
S. Hamieh ◽  
J. Qi ◽  
D. Siminovitch ◽  
M. K. Ali
Keyword(s):  
Quantum System ◽  
Bipartite Quantum System ◽  
Classical Correlations

scholarly journals Negative quantum conditional entropy and the entanglement measure of a kind of mixed state of bipartite quantum system

2007 ◽  
Vol 56 (7) ◽  
pp. 3937
Author(s):  
Zhou Bing-Ju ◽  
Liu Xiao-Juan ◽  
Fang Mao-Fa ◽  
Zhou Qing-Ping ◽  
Liu Ming-Wei
Keyword(s):  
Quantum System ◽  
Mixed State ◽  
Conditional Entropy ◽  
Entanglement Measure ◽  
Bipartite Quantum System ◽  
Quantum Conditional Entropy

scholarly journals Daemonic Ergotropy: Generalised Measurements and Multipartite Settings

Entropy ◽  
2019 ◽  
Vol 21 (8) ◽  
pp. 771 ◽  
Author(s):  
Fabian Bernards ◽  
Matthias Kleinmann ◽  
Otfried Gühne ◽  
Mauro Paternostro
Keyword(s):  
Quantum System ◽  
Information Gain ◽  
Quantum Correlations ◽  
Maximum Energy ◽  
Extraction Protocol ◽  
Original Definition ◽  
Maximum Work ◽  
Classical Correlations ◽  
Projective Measurements ◽  
Classical States

Recently, the concept of daemonic ergotropy has been introduced to quantify the maximum energy that can be obtained from a quantum system through an ancilla-assisted work extraction protocol based on information gain via projective measurements [G. Francica et al., npj Quant. Inf. 3, 12 (2018)]. We prove that quantum correlations are not advantageous over classical correlations if projective measurements are considered. We go beyond the limitations of the original definition to include generalised measurements and provide an example in which this allows for a higher daemonic ergotropy. Moreover, we propose a see-saw algorithm to find a measurement that attains the maximum work extraction. Finally, we provide a multipartite generalisation of daemonic ergotropy that pinpoints the influence of multipartite quantum correlations, and study it for multipartite entangled and classical states.

scholarly journals Locally indistinguishable orthogonal product bases in arbitrary bipartite quantum system

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Guang-Bao Xu ◽  
Ying-Hui Yang ◽  
Qiao-Yan Wen ◽  
Su-Juan Qin ◽  
Fei Gao
Keyword(s):  
Quantum System ◽  
Bipartite Quantum System ◽  
Orthogonal Product

Mosaic number of knots

2014 ◽  
Vol 23 (13) ◽  
pp. 1450069 ◽  
Author(s):  
Hwa Jeong Lee ◽  
Kyungpyo Hong ◽  
Ho Lee ◽  
Seungsang Oh
Keyword(s):  
Quantum System ◽  
Upper Bound ◽  
Crossing Number ◽  
System A ◽  
Definition Of ◽  
Hopf Link

Lomonaco and Kauffman developed knot mosaics to give a definition of a quantum knot system. This definition is intended to represent an actual physical quantum system. A knot n-mosaic is an n × n matrix of 11 kinds of specific mosaic tiles representing a knot or a link. The mosaic number m(K) of a knot K is the smallest integer n for which K is representable as a knot n-mosaic. In this paper, we establish an upper bound on the mosaic number of a knot or a link K in terms of the crossing number c(K). Let K be a nontrivial knot or a non-split link except the Hopf link. Then m(K) ≤ c(K) + 1. Moreover if K is prime and non-alternating except [Formula: see text] link, then m(K) ≤ c(K) - 1.

Communication

2021 ◽  
pp. 223-260
Author(s):  
Jochen Rau
Keyword(s):  
Quantum Information ◽  
Quantum System ◽  
Quantum State ◽  
Upper Bound ◽  
Carrying Capacity ◽  
Quantitative Measure ◽  
Important Application ◽  
Classical Information ◽  
Mathematical Properties ◽  
Cryptographic Keys

This chapter introduces the notions of classical and quantum information and discusses simple protocols for their exchange. It defines the entropy as a quantitative measure of information, and investigates its mathematical properties and operational meaning. It discusses the extent to which classical information can be carried by a quantum system and derives a pertinent upper bound, the Holevo bound. One important application of quantum communication is the secure distribution of cryptographic keys; a pertinent protocol, the BB84 protocol, is discussed in detail. Moreover, the chapter explains two protocols where previously shared entanglement plays a key role, superdense coding and teleportation. These are employed to effectively double the classical information carrying capacity of a qubit, or to transmit a quantum state with classical bits, respectively. It is shown that both protocols are optimal.

Quantum Subspace Measurements

2007 ◽  
Vol 14 (01) ◽  
pp. 117-126 ◽  
Author(s):  
Neal G. Anderson
Keyword(s):  
Hilbert Space ◽  
Quantum System ◽  
Upper Bound ◽  
Quantum Measurements ◽  
Positive Operators ◽  
Accessible Information ◽  
Measured System ◽  
Characteristic Features

Fundamental studies of quantum measurements and their capacity to acquire information are typically based on scenarios in which the full Hilbert space of the measured quantum system is open to measurement interactions. In this work, we consider a class of incomplete quantum measurements — quantum subspace measurements (QSM's) — for which all measurement interactions are restricted to an arbitrary but specified subspace of the measured system Hilbert space. We define QSM's formally through a condition on the measurement Hamiltonian, obtain forms for the post-measurement states and positive operators (POVM elements) associated with QSM's acting in a specified subspace, and upper bound the accessible information for such measurements. Characteristic features of QSM's are identified and discussed.

Lasing process in a closed bipartite quantum system: A thermodynamical analysis

2010 ◽  
Vol 81 (6) ◽  
Author(s):  
G. Waldherr ◽  
G. Mahler
Keyword(s):  
Quantum System ◽  
Bipartite Quantum System ◽  
System A
Sign in / Sign up

Export Citation Format

Share Document