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Related papers: Optimizing Measurements Sequences for Quantum Stat…

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Quantum coherence is one of the most significant theories in quantum physics. Ordering states with various coherence measures is an intriguing task in quantification theory of coherence. In this paper, we study this problem by use of four…

Quantum Physics · Physics 2018-03-08 Long-Mei Yang , Bin Chen , Shao-Ming Fei , Zhi-Xi Wang

When measuring phase of quantum states of light, the optimal single-shot measurement implements projection on the un-physical phase states. If we want to improve the precision further we need to accept a reduced probability of success,…

Quantum Physics · Physics 2015-06-16 Petr Marek

State estimation for discrete-time linear systems with quantized measurements is addressed. By exploiting the set-theoretic nature of the information provided by the quantizer, the problem is cast in the set membership estimation setting.…

Systems and Control · Electrical Eng. & Systems 2023-12-05 Marco Casini , Andrea Garulli , Antonio Vicino

We investigate the optimal estimation of quantum expectation value of a physical observable, which minimizes a mean error with respect to general measure of deviation, when a finite number of copies of a pure state are prepared. If pure…

Quantum Physics · Physics 2007-05-23 Minoru Horibe , Akihisa Hayashi , Takaaki Hashimoto

Precision metrology underpins scientific and technological advancements. Quantum metrology offers a pathway to surpass classical sensing limits by leveraging quantum states and measurement strategies. However, measuring multiple…

The problem concerning the minimum time for an initial state to evolve up to a target state plays an important role in the Classic Optimal Control theory. In the quantum context, as quantum states are so sensitive to environmental…

Quantum Physics · Physics 2015-09-01 Alexandre Coutinho Lisboa , Jose Roberto Castilho Piqueira

We study quantum measurement with preselection and postselection, and derive the precise expressions of the measurement results without any restriction on the coupling strength between the system and the measuring device. For a qubit…

Quantum Physics · Physics 2011-11-18 Xuanmin Zhu , Yuxiang Zhang , Shengshi Pang , Chang Qiao , Quanhui Liu , Shengjun Wu

We investigate the quantum state discrimination task for sets of linear independent pure states with an intrinsic ordering. This structured discrimination problems allow for a novel scheme that provides a certified level of error, that is,…

Quantum Physics · Physics 2019-11-06 Esteban Martínez-Vargas , Ramon Munoz-Tapia

In this paper, we present a thought experiment that demonstrates that the equivalence of quantum reduced states and statistical mixed states of ensembles is not merely a simple mathematical formulation in quantum mechanics, but rather…

Quantum Physics · Physics 2025-04-18 Zhihong Zuo

We discuss the problem of finding the best measurement strategy for estimating the value of a quantum system parameter. In general the optimum quantum measurement, in the sense that it maximizes the quantum Fisher information and hence…

Quantum Physics · Physics 2017-02-07 Esteban Martinez , Carlos Pineda , François Leyvraz , Pablo Barberis-Blostein

We address a broad class of optimization problems of finding quantum measurements, which includes the problems of finding an optimal measurement in the Bayes criterion and a measurement maximizing the average success probability with a…

Quantum Physics · Physics 2015-06-23 Kenji Nakahira , Kentaro Kato , Tsuyoshi Sasaki Usuda

Extracting information from quantum devices has long been a crucial problem in the field of quantum mechanics. By performing elaborate measurements, quantum state tomography, an important and fundamental tool in quantum science and…

Quantum Physics · Physics 2022-06-24 Yu Wang , Keren Li

Mutually unbiased bases determine an optimal set of measurements to extract complete information about the quantum state of a system. However, quite often a priori information about the state exist, making some of the measurement bases…

Quantum Physics · Physics 2015-06-12 A. B. Klimov , G. Bjork , L. L. Sanchez-Soto

We consider the problem of quantum state certification, where we are given the description of a mixed state $\sigma \in \mathbb{C}^{d \times d}$, $n$ copies of a mixed state $\rho \in \mathbb{C}^{d \times d}$, and $\varepsilon > 0$, and we…

Quantum Physics · Physics 2022-10-21 Sitan Chen , Brice Huang , Jerry Li , Allen Liu

The recently established resource theory of quantum coherence allows for a quantitative understanding of the superposition principle, with applications reaching from quantum computing to quantum biology. While different quantifiers of…

Quantum phase estimation is fundamental to advancing quantum science and technology. While much of the research has concentrated on estimating a single phase, the simultaneous estimation of multiple phases can yield significantly enhanced…

Quantum Physics · Physics 2025-03-21 Marco Barbieri , Ilaria Gianani , Aaron Z. Goldberg , Luis L. Sánchez-Soto

Quantum scale estimation, as introduced and explored here, establishes the most precise framework for the estimation of scale parameters that is allowed by the laws of quantum mechanics. This addresses an important gap in quantum metrology,…

Quantum Physics · Physics 2022-11-18 Jesús Rubio

In this study the determinant of the average quadratic error matrix is used as the measure of state estimation efficiency. This quantity is easily computable in some cases, so it gives us a reasonable tool to find optimal measurement setup…

Quantum Physics · Physics 2012-01-10 Denes Petz , Laszlo Ruppert

In almost all quantum applications, one of the key steps is to verify that the fidelity of the prepared quantum state meets expectations. In this Letter, we propose a new approach solving this problem using machine-learning techniques.…

Quantum Physics · Physics 2021-09-28 Xiaoqian Zhang , Maolin Luo , Zhaodi Wen , Qin Feng , Shengshi Pang , Weiqi Luo , Xiaoqi Zhou

Quantum metrology stands as a leading application of quantum science and technology, yet noise often constrains its precision and sensitivity. In near-term quantum metrology, existing protocols largely depend on virtual state purification,…

Quantum Physics · Physics 2025-12-03 Xiaodie Lin , Haidong Yuan