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Related papers: Universal quantum state merging

200 papers

We investigate the irreversibility of entanglement distillation for a symmetric d-1 parameter family of mixed bipartite quantum states acting on Hilbert spaces of arbitrary dimension d x d. We prove that in this family the entanglement cost…

Quantum Physics · Physics 2009-11-10 K. G. H. Vollbrecht , R. F. Werner , M. M. Wolf

We show that the process of entanglement distillation is irreversible by showing that the entanglement cost of a bound entangled state is finite. Such irreversibility remains even if extra pure entanglement is loaned to assist the…

Quantum Physics · Physics 2009-11-07 G. Vidal , J. I. Cirac

We present an alternative approach to the derivation of benchmarks for quantum channels, such as memory or teleportation channels. Using the concept of effective entanglement and the verification thereof, a testing procedure is derived…

Quantum Physics · Physics 2009-10-09 Hauke Häseler , Norbert Lütkenhaus

In the paper, we show that when a quantum state can be decomposed as a convex combination of locally orthogonal mixed states, its entanglement can be decomposed into the entanglement of these mixed states without losing them. The obtained…

Quantum Physics · Physics 2022-07-12 Sunho Kim , Junde Wu , Lin Zhang , Minhyung Cho

Most states in the Hilbert space are maximally entangled. This fact has proven useful to investigate - among other things - the foundations of statistical mechanics. Unfortunately, most states in the Hilbert space of a quantum many body…

Quantum Physics · Physics 2015-05-30 Alioscia Hamma , Siddhartha Santra , Paolo Zanardi

The ``entanglement of formation'' of a mixed state of a bipartite quantum system can be defined in terms of the number of pure singlets needed to create the state with no further transfer of quantum information. We find an exact formula for…

Quantum Physics · Physics 2009-01-23 Scott Hill , William K. Wootters

It is often argued that entanglement is at the root of the speedup for quantum compared to classical computation, and that one needs a sufficient amount of entanglement for this speedup to be manifest. In measurement-based quantum computing…

Quantum Physics · Physics 2015-05-13 D. Gross , S. Flammia , J. Eisert

We find that a bipartite quantum state is entangled if and only if it is quantum coherent with respect to complete bases of states in the corresponding system that are distinguishable under local quantum operations and classical…

Quantum Physics · Physics 2022-01-19 Asmitha Mekala , Ujjwal Sen

The creation of complex entangled states, resources that enable quantum computation, can be achieved via simple 'probabilistic' operations which are individually likely to fail. However, typical proposals exploiting this idea carry a severe…

Quantum Physics · Physics 2013-05-29 Yuichiro Matsuzaki , Simon C Benjamin , Joseph Fitzsimons

Quantifying the minimum entanglement needed to prepare quantum states and implement quantum processes is a key challenge in quantum information theory. In this work, we develop computable and faithful lower bounds on the entanglement cost…

Quantum Physics · Physics 2025-05-08 Xin Wang , Mingrui Jing , Chengkai Zhu

The bipartite entanglement of a pure quantum state is known to be characterized by its Schmidt decomposition. In particular the state is maximally entangled when all the Schmidt coefficients are equal. We point out a convenient method which…

Quantum Physics · Physics 2008-01-09 M. Bhattacharya

We question the role of entanglement in masking quantum information contained in a set of mixed quantum states. We first show that a masker that can mask any two single-qubit pure states, can mask the entire set of mixed states comprising…

Quantum Physics · Physics 2025-06-24 Debarupa Saha , Priya Ghosh , Ujjwal Sen

The emerging quantum technologies rely on our ability to establish and control quantum systems in nonclassical states, exhibiting entanglement and quantum coherence. It is thus crucial to understand how entanglement and coherence can be…

Quantum Physics · Physics 2022-06-22 Masaya Takahashi , Swapan Rana , Alexander Streltsov

We study entanglement distillation and dilution of states and channels in the single-shot regime. With the help of a recently introduced conversion distance, we provide compact closed-form expressions for the dilution and distillation of…

Quantum Physics · Physics 2023-12-29 Thomas Theurer , Kun Fang , Gilad Gour

Multipartite entanglement determines the strength and range of interactions in many-body quantum systems. Yet, it is hard to evaluate it, due to the complex structures of quantum states. Here, we introduce a generic method to quantify the k…

Quantum Physics · Physics 2026-02-16 Francois Payn , Michele Minervini , Davide Girolami

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement is explored for bi-partite and multi-partite pure and mixed states.…

Quantum Physics · Physics 2009-05-18 Tzu-Chieh Wei

As quantum technologies advance, the ability to generate increasingly large quantum states has experienced rapid development. In this context, the verification and estimation of large entangled systems represents one of the main challenges…

Quantum Physics · Physics 2022-03-30 Joshua Morris , Valeria Saggio , Aleksandra Gočanin , Borivoje Dakić

We investigate the issue of speed-up and the necessity of entanglement in Grover's quantum search algorithm. We find that in a pure state implementation of Grover's algorithm entanglement is present even though the initial and target states…

Quantum Physics · Physics 2007-05-23 Samuel L. Braunstein , Arun K. Pati

The cluster state, the highly entangled state that is the central resource for one-way quantum computing, can be efficiently generated in a variety of physical implementations via global nearest-neighbor interactions. In practice, a…

Quantum Physics · Physics 2008-03-10 Michael C. Garrett , David L. Feder

In quantum information theory, it is widely believed that entanglement concentration for bipartite pure states is asymptotically reversible. In order to examine this, we give a precise formulation of the problem, and show a trade-off…

Quantum Physics · Physics 2013-10-01 Wataru Kumagai , Masahito Hayashi