English
Related papers

Related papers: Probing the geometry of correlation matrices with …

200 papers

We investigate the norms of the Bloch vectors for any quantum state with subsystems less than or equal to four. Tight upper bounds of the norms are obtained, which can be used to derive tight upper bounds for entanglement measure defined by…

Quantum Physics · Physics 2019-03-27 Ming Li , Zong Wang , Jing Wang , Shuqian Shen , Shao-ming Fei

The uncertainty relation is one of the key ingredients of quantum theory. Despite the great efforts devoted to this subject, most of the variance-based uncertainty relations are state-dependent and suffering from the triviality problem of…

Quantum Physics · Physics 2018-03-08 Chen Qian , Jun-Li Li , Cong-Feng Qiao

Entanglement measures quantify the amount of quantum entanglement that is contained in quantum states. Typically, different entanglement measures do not have to be partially ordered. The presence of a definite partial order between two…

Quantum Physics · Physics 2022-08-30 Danko D. Georgiev , Stanley P. Gudder

A quantum state's entanglement across a bipartite cut can be quantified with entanglement entropy or, more generally, Schmidt norms. Using only Schmidt decompositions, we present a simple iterative algorithm to maximize Schmidt norms.…

Quantum Physics · Physics 2018-06-14 Robin Reuvers

When studying the geometry of quantum states, it is acknowledged that mixed states can be distinguished by infinitely many metrics. Unfortunately, this freedom causes metric-dependent interpretations of physically significant geometric…

Quantum Physics · Physics 2024-02-07 Paul M. Alsing , Carlo Cafaro , Domenico Felice , Orlando Luongo

Summary. A simple derivation of finite Schmidt decomposition of pure states describing finite dimensional systems interacting with the infinite dimensional ones is presented. In particular, maximally entangled pure states in such systems…

Quantum Physics · Physics 2018-03-28 Roman Gielerak

A general framework is developed for separating classical and quantum correlations in a multipartite system. Entanglement is defined as the difference in the correlation information encoded by the state of a system and a suitably defined…

Quantum Physics · Physics 2007-05-23 M. Hossein Partovi

Entanglement is a central resource in quantum information science, yet its structure in high dimensions remains notoriously difficult to characterize. One of the few general results on high-dimensional entanglement is given by peel-off…

Quantum Physics · Physics 2025-09-10 Robin Krebs , Mariami Gachechiladze

We provide a one-to-one map between the spin correlations and certain three-dimensional shapes, analogous to the map between single spins and Bloch vectors, and demonstrate its utility. Much as one can reason geometrically about dynamics…

We study the mathematical structures and relations among some quantities in the theory of quantum entanglement, such as separability, weak Schmidt decompositions, Hadamard matrices etc.. We provide an operational method to identify the…

Quantum Physics · Physics 2014-02-26 Bobo Hua , Shaoming Fei , Juergen Jost , Xianqing Li-Jost

Experimental procedures are presented for the rapid detection of entanglement of unknown arbitrary quantum states. The methods are based on the entanglement criterion using accessible correlations and the principle of correlation…

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

We extend Bloch Sphere formalism to pure two qubit systems. Combining insights from Geometric Algebra and analysis of entanglement in different conjugate bases we identify Two Bloch Sphere geometry that is suitable for representing…

Quantum Physics · Physics 2024-03-19 Stanislav Filatov , Marcis Auzinsh

Measurements with randomly chosen settings determine many important properties of quantum states without the need for a shared reference frame or calibration. They naturally emerge in the context of quantum communication and quantum…

Randomized measurement protocols, including classical shadows, entanglement tomography, and randomized benchmarking are powerful techniques to estimate observables, perform state tomography, or extract the entanglement properties of quantum…

Quantum Physics · Physics 2024-04-03 Jacob Bringewatt , Jonathan Kunjummen , Niklas Mueller

Given a quantum system on many qubits split into a few different parties, how many total correlations are there between these parties? Such a quantity, aimed to measure the deviation of the global quantum state from an uncorrelated state…

Quantum Physics · Physics 2022-02-15 Zhenhuan Liu , Pei Zeng , You Zhou , Mile Gu

Separability is an important problem in theory of quantum entanglement. By using the Bloch representation of quantum states in terms of the Heisenberg-Weyl observable basis, we present a new separability criterion for bipartite quantum…

Quantum Physics · Physics 2020-02-04 Jingmei Chang , Meiyu Cui , Tinggui Zhang , Shao-Ming Fei

The complexity of quantum many-body systems is manifested in the vast diversity of their correlations, making it challenging to distinguish the generic from the atypical features. This can be addressed by analyzing correlations through…

Quantum Physics · Physics 2023-09-04 Daniel Haag , Flavio Baccari , Georgios Styliaris

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, already present in a number of settings (see Shimony 1995 and…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Paul M. Goldbart

Geometry and topology are fundamental to modern condensed matter physics, but their precise connection in quantum systems remains incompletely understood. Here, we develop an analytical scheme for calculating the curvature of the quantum…

Quantum Physics · Physics 2025-10-20 Shin-Ming Huang