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Related papers: Limits on Parameter Estimation of Quantum Channels

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We experimentally analyzed the statistical errors in quantum-state estimation and examined whether their lower bound, which is derived from the Cramer-Rao inequality, can be truly attained or not. In the experiments, polarization states of…

Quantum Physics · Physics 2013-05-29 Koji Usami , Yoshihiro Nambu , Yoshiyuki Tsuda , Keiji Matsumoto , Kazuo Nakamura

The quantum approximate optimization algorithm (QAOA) is known for its capability and universality in solving combinatorial optimization problems on near-term quantum devices. The results yielded by QAOA depend strongly on its initial…

Quantum Physics · Physics 2022-09-29 Xinwei Lee , Ningyi Xie , Yoshiyuki Saito , Dongsheng Cai , Nobuyoshi Asai

To achieve the joint active and passive beamforming gains in the reconfigurable intelligent surface assisted millimeter wave system, the reflected cascade channel needs to be accurately estimated. Many strategies have been proposed in the…

Information Theory · Computer Science 2021-09-22 Yiming Liu , Erwu Liu , Rui Wang , Zhu Han , Binyu Lu

Parameterized quantum circuits can be used as quantum neural networks and have the potential to outperform their classical counterparts when trained for addressing learning problems. To date, much of the results on their performance on…

Quantum Physics · Physics 2023-04-13 Junyu Liu , Khadijeh Najafi , Kunal Sharma , Francesco Tacchino , Liang Jiang , Antonio Mezzacapo

In this work, we study Bayesian quantum parameter estimation given a finite number of uses of the process encoding one or more unknown physical quantities. For multiple uses, it is conventional to classify quantum metrological protocols as…

Quantum Physics · Physics 2026-02-11 Erik L. André , Jessica Bavaresco , Mohammad Mehboudi

This paper considers a sequential sensor scheduling and remote estimation problem with multiple communication channels. Departing from the classical remote estimation paradigm, which involves one communication channel (noiseless or noisy),…

Systems and Control · Computer Science 2018-04-10 Xiaobin Gao , Emrah Akyol , Tamer Basar

Noise affects the performance of quantum technologies, hence the importance of elaborating operative figures of merit that can capture its impact in exact terms. In quantum metrology, the introduction of the Fisher information measurement…

Quantum Physics · Physics 2024-09-30 Francesco Albarelli , Ilaria Gianani , Marco G. Genoni , Marco Barbieri

We introduce a quantum sensing protocol for detecting the parameters characterizing the phase space displacement by using a single trapped ion as a quantum probe. We show that thanks to the laser-induced coupling between the ion's internal…

Quantum Physics · Physics 2018-03-13 Peter A. Ivanov , Nikolay V. Vitanov

The Cram\'er-Rao bound (CRB), a well-known lower bound on the performance of any unbiased parameter estimator, has been used to study a wide variety of problems. However, to obtain the CRB, requires an analytical expression for the…

Machine Learning · Computer Science 2022-10-11 Hai Victor Habi , Hagit Messer , Yoram Bresler

This paper considers a sequential estimation and sensor scheduling problem with one sensor and one estimator. The sensor makes sequential observations about the state of an underlying memoryless stochastic process, and makes a decision as…

Systems and Control · Computer Science 2016-11-17 Xiaobin Gao , Emrah Akyol , Tamer Basar

The estimation of multiple parameters in quantum metrology is important for a vast array of applications in quantum information processing. However, the unattainability of fundamental precision bounds for incompatible observables has…

Quantum Physics · Physics 2021-02-17 Jasminder S. Sidhu , Yingkai Ouyang , Earl T. Campbell , Pieter Kok

Critical properties of a quantum system are recognized as valuable resources for quantum metrology. In this work, we investigate the criticality-enhanced sensing in a quantum Rabi triangle system, which exhibits multiple phases. Around the…

Quantum Physics · Physics 2025-11-04 Yuyang Tang , Yu Yang , Min An , Fuli Li

Protocols for discriminating between a pair of channels or for estimating a channel parameter can often be aided by adaptivity or by entanglement between the probe states. This can make it difficult to bound the best possible performance…

Quantum Physics · Physics 2021-10-07 Jason L. Pereira , Leonardo Banchi , Stefano Pirandola

We consider estimating the parameter associated with the qubit depolarizing channel when the available initial states that might be employed are mixed. We use quantum Fisher information as a measure of the accuracy of estimation to compare…

Quantum Physics · Physics 2015-10-28 David Collins , Jaimie Stephens

Communication over a fully quantum relay channel is considered. We establish three bounds based on different coding strategies, i.e., partial decode-forward, measure-forward, and assist-forward. Using the partial-decode forward strategy,…

Quantum Physics · Physics 2025-05-22 Uzi Pereg

Making judicious channel access and transmission scheduling decisions is essential for improving performance as well as energy and spectral efficiency in multichannel wireless systems. This problem has been a subject of extensive study in…

Machine Learning · Computer Science 2015-04-07 Yang Liu , Mingyan Liu

Gaussian channels with memory and with noiseless feedback have been widely studied in the information theory literature. However, a coding scheme to achieve the feedback capacity is not available. In this paper, a coding scheme is proposed…

Information Theory · Computer Science 2007-07-13 Jialing Liu , Nicola Elia

A Cramer-Rao bound (CRB) for semi-blind channel estimators in redundant block transmission systems is derived. The derived CRB is valid for any system adopting a full-rank linear redundant precoder, including the popular cyclic-prefixed…

Information Theory · Computer Science 2012-09-20 Yen-Huan Li , Borching Su , Ping-Cheng Yeh

The quantum Cram\'er-Rao bound is a cornerstone of modern quantum metrology, as it provides the ultimate precision in parameter estimation. In the multiparameter scenario, this bound becomes a matrix inequality, which can be cast to a…

Quantum Physics · Physics 2021-09-15 Aaron Z. Goldberg , Luis L. Sánchez-Soto , Hugo Ferretti

In this work we probe the impact of channel estimation on the performance of quantum LDPC codes. Our channel estimation is based on an optimal estimate of the relevant decoherence parameter via its quantum Fisher information. Using…

Information Theory · Computer Science 2012-02-03 Yixuan Xie , Jun Li , Robert Malaney , Jinhong Yuan