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Related papers: Comparing the states of many quantum systems

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We study quantum state estimation problems where the reference system with respect to which the state is measured should itself be treated quantum mechanically. In this situation, the difference between the system and the reference tends to…

Quantum Physics · Physics 2013-01-22 N. Gisin , S. Iblisdir

Suppose you receive a sequence of qubits where each qubit is guaranteed to be in one of two pure states, but you do not know what those states are. Your task is to determine the states. This can be viewed as a kind of quantum state learning…

In the realm of quantum information processing, the efficient characterization of entangled states poses an overwhelming challenge, rendering the traditional methods including quantum tomography unfeasible and impractical. To tackle this…

Quantum Physics · Physics 2025-12-09 Ye-Chao Liu , Jiangwei Shang

Quantum hypothesis testing (QHT) provides an effective method to discriminate between two quantum states using a two-outcome positive operator-valued measure (POVM). Two types of decision errors in a QHT can occur. In this paper we focus on…

Quantum Physics · Physics 2023-07-13 Yi Shen , Carlo Maria Scandolo , Lin Chen

Quantum state discrimination is a fundamental concept in quantum information theory, which refers to a class of techniques to identify a specific quantum state through a positive operator-valued measure. In this work, we investigate how…

Quantum Physics · Physics 2025-07-09 Hyunho Cha , Jungwoo Lee

Quantum state discrimination depicts the general progress of extracting classical information from quantum systems. We show that quantum state discrimination can be realized in a device-independent scenario using tools of self-testing…

Quantum Physics · Physics 2024-01-25 Xinyu Qiu , Lin Chen

Experimental determination of an unknown quantum state usually requires several incompatible measurements. However, it is also possible to determine the full quantum state from a single, repeated measurement. For this purpose, the quantum…

Quantum Physics · Physics 2008-03-25 Xinhua Peng , Jiangfeng Du , Dieter Suter

This work investigates which sets of quantum states give rise to the highest achievable success probability in minimum-error state discrimination if multiple copies of the unknown state are given. Specifically, we consider uniformly…

We introduce a protocol addressing the conformance test problem, which consists in determining whether a process under test conforms to a reference one. We consider a process to be characterized by the set of end-product it produces, which…

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 present a generic study of unambiguous discrimination between two mixed quantum states. We derive operational optimality conditions and show that the optimal measurements can be classified according to their rank. In Hilbert space…

Quantum Physics · Physics 2010-03-10 M. Kleinmann , H. Kampermann , D. Bruss

In this paper, we study a fault-tolerant control for systems consisting of multiple homogeneous components such as parallel processing machines. This type of system is often more robust to uncertainty compared to those with a single…

Optimization and Control · Mathematics 2020-12-03 Jalal Arabneydi , Amir G. Aghdam

Roa et al. showed that quantum state discrimination between two nonorthogonal quantum states does not require quantum entanglement but quantum dissonance only. We find that quantum coherence can also be utilized for unambiguous quantum…

Quantum Physics · Physics 2021-08-10 Sunho Kim , Longsuo Li , Asutosh Kumar , Chunhe Xiong , Sreetama Das , Ujjwal Sen , Arun Kumar Pati , Junde Wu

State discrimination is a useful test problem with which to clarify the power and limitations of different classes of measurement. We consider the problem of discriminating between given states of a bi-partite quantum system via sequential…

Quantum Physics · Physics 2017-09-25 Sarah Croke , Stephen M. Barnett , Graeme Weir

Operator quantum error correction provides a unified framework for the known techniques of quantum error correction such as the standard error correction model, the method of decoherence-free subspaces, and the noiseless subsystem method.…

Quantum Physics · Physics 2014-04-25 Ri Qu , Bing-jian Shang , Yan-ru Bao , Yi-ping Ma

A key concept of quantum information theory is that accessing information encoded in a quantum system requires us to discriminate between several possible states the system could be in. A natural generalization of this problem, namely,…

Quantum Physics · Physics 2025-01-07 Tathagata Gupta , Shayeef Murshid , Vincent Russo , Somshubhro Bandyopadhyay

This expository article gives an overview of the theory of hypothesis testing of quantum states in finite dimensional Hilbert spaces. Optimal measurement strategy for testing binary quantum hypotheses, which result in minimum error…

Quantum Physics · Physics 2018-03-14 J. Prabhu Tej , Syed Raunaq Ahmed , A. R. Usha Devi , A. K. Rajagopal

Quantum error correction protects quantum information against environmental noise. When using qubits, a measure of quality of a code is the maximum number of errors that it is able to correct. We show that a suitable notion of ``number of…

Quantum Physics · Physics 2007-05-23 Emanuel Knill , Raymond Laflamme , Lorenza Viola

It is a central fact in quantum mechanics that non-orthogonal states cannot be distinguished perfectly. This property ensures the security of quantum key distribution. It is therefore an important task in quantum communication to design and…

Quantum Physics · Physics 2023-11-27 Lorcan O. Conlon , Falk Eilenberger , Ping Koy Lam , Syed M. Assad

Error probability is a popular and well-studied optimization criterion in discriminating non-orthogonal quantum states. It captures the threat from an adversary who can only query the actual state once. However, when the adversary is able…

Quantum Physics · Physics 2015-05-11 Weien Chen , Yongzhi Cao , Hanpin Wang , Yuan Feng