English
Related papers

Related papers: Toward Instance-Optimal State Certification With I…

200 papers

We consider the problem of discriminating between states of a specified set with maximum confidence. For a set of linearly independent states unambiguous discrimination is possible if we allow for the possibility of an inconclusive result.…

Quantum Physics · Physics 2007-05-23 Sarah Croke , Erika Andersson , Stephen M. Barnett , Claire R. Gilson , John Jeffers

The certification of quantum resources is a critical tool in the development of quantum information processing. In particular, quantum state verification is a fundamental building block for communication and computation applications,…

It is shown that local distinguishability of orthogonal mixed states can be completely characterized by local distinguishability of their supports irrespective of entanglement and mixedness of the states. This leads to two kinds of upper…

Quantum Physics · Physics 2012-04-20 Somshubhro Bandyopadhyay

It is well-known that observing nonlocal correlations allows us to draw conclusions about the quantum systems under consideration. In some cases this yields a characterisation which is essentially complete, a phenomenon known as…

Quantum Physics · Physics 2020-04-02 Tim Coopmans , Jędrzej Kaniewski , Christian Schaffner

Unpredictability, or randomness, of the outcomes of measurements made on an entangled state can be certified provided that the statistics violate a Bell inequality. In the standard Bell scenario where each party performs a single…

Quantum Physics · Physics 2017-03-01 F. J. Curchod , M. Johansson , R. Augusiak , M. J. Hoban , P. Wittek , A. Acín

Quantum Stein's Lemma is a cornerstone of quantum statistics and concerns the problem of correctly identifying a quantum state, given the knowledge that it is one of two specific states ($\rho$ or $\sigma$). It was originally derived in the…

Quantum Physics · Physics 2017-02-10 Nilanjana Datta , Yan Pautrat , Cambyse Rouzé

In this paper, we show that $\Theta(\mathrm{poly}(n)\cdot\frac{4^n}{\epsilon^2})$ is the sample complexity of testing whether two $n$-qubit quantum states $\rho$ and $\sigma$ are identical or $\epsilon$-far in trace distance using…

Quantum Physics · Physics 2020-09-25 Nengkun Yu

We analyze to what extent it is possible to copy arbitrary states of a two-level quantum system. We show that there exists a "universal quantum copying machine", which approximately copies quantum mechanical states in such a way that the…

Quantum Physics · Physics 2009-10-30 Vladimir Buzek , Mark Hillery

We find optimality conditions for testers in discrimination of quantum channels. These conditions are obtained using semidefinite programming and are similar to optimality conditions for POVMs obtained by Holevo for ensembles of quantum…

Quantum Physics · Physics 2017-01-26 Anna Jenčová , Martin Plávala

The certification of quantum systems is essential for emerging quantum technologies, particularly in quantum communication, networks, and distributed computing, where maintaining a common reference frame across distant nodes poses…

Quantum Physics · Physics 2026-04-17 Julian Eisfeld , Nikolai Wyderka

Coherence, the superposition of orthogonal quantum states, is indispensable in various quantum processes. Inspired by the polynomial invariant for classifying and quantifying entanglement, we first define polynomial coherence measure and…

Quantum Physics · Physics 2018-09-07 You Zhou , Qi Zhao , Xiao Yuan , Xiongfeng Ma

Gaussian states are widely regarded as one of the most relevant classes of continuous-variable (CV) quantum states, as they naturally arise in physical systems and play a key role in quantum technologies. This motivates a fundamental…

Authentication of quantum sources is a crucial task in building reliable and efficient protocols for quantum-information processing. Steady progress vis-\`{a}-vis verification of quantum devices in the scenario with fully characterized…

Quantum Physics · Physics 2022-02-08 Aleksandra Gočanin , Ivan Šupić , Borivoje Dakić

Given a Bell inequality, if its maximal quantum violation can be achieved only by a single set of measurements for each party or a single quantum state, up to local unitaries, one refers to such a phenomenon as self-testing. For instance,…

Quantum Physics · Physics 2021-09-29 Shin-Liang Chen , Huan-Yu Ku , Wenbin Zhou , Jordi Tura , Yueh-Nan Chen

Quantum state tomography is the task of inferring the state of a quantum system by appropriate measurements. Since the frequency distributions of the outcomes of any finite number of measurements will generally deviate from their asymptotic…

Quantum Physics · Physics 2012-11-08 Matthias Christandl , Renato Renner

We propose upper and lower bounds on the maximum success probability for discriminating given quantum states. The proposed upper bound is obtained from a suboptimal solution to the dual problem of the corresponding optimal state…

Quantum Physics · Physics 2018-01-12 Kenji Nakahira , Tsuyoshi Sasaki Usuda , Kentaro Kato

Understanding the power and limitations of classical and quantum information and how they differ is a fundamental endeavor. In property testing of distributions, a tester is given samples over a typically large domain $\{0,1\}^n$. An…

Quantum Physics · Physics 2024-11-26 Fernando Granha Jeronimo , Nir Magrafta , Joseph Slote , Pei Wu

Quantum metrology explores quantum effects to improve the measurement accuracy of some physical quantities beyond the classical limit. However, due to the interaction between the system and the environment, the decoherence can significantly…

Quantum Physics · Physics 2024-05-07 Cheng-Ge Liu , Cong-Wei Lu , Na-Na Zhang , Qing Ai

Convex functions of quantum states play a key role in quantum physics, with examples ranging from Bell inequalities to von Neumann entropy. However, in experimental scenarios, direct measurements of these functions are often impractical. We…

Quantum Physics · Physics 2024-08-21 Leonardo Zambrano , Donato Farina , Egle Pagliaro , Marcio M. Taddei , Antonio Acin

The uncertainty principle may be considered as giving rise to the notion of incompatibility of observables. A pack of quantum measurements that cannot be measured simultaneously is said to form a set of incompatible measurements. Every set…

Quantum Physics · Physics 2024-01-19 Kornikar Sen , Saronath Halder , Ujjwal Sen