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Related papers: Mixed state discrimination using optimal control

200 papers

We study the problem of discriminating between non-orthogonal quantum states with least probability of error. We demonstrate that this problem can be simplified if we solve for the error itself rather than solving directly for the optimal…

Quantum Physics · Physics 2009-11-10 Kieran Hunter

Entangled atomic states, such as spin squeezed states, represent a promising resource for a new generation of quantum sensors and atomic clocks. We demonstrate that optimal control techniques can be used to substantially enhance the degree…

Quantum Physics · Physics 2016-02-03 T. Pichler , T. Caneva , S. Montangero , M. D. Lukin , T. Calarco

In the task of discriminating between nonorthogonal quantum states from multiple copies, the key parameters are the error probability and the resources (number of copies) used. Previous studies have considered the task of minimizing the…

Quantum discrimination and estimation are pivotal for many quantum technologies, and their performance depends on the optimal choice of probe state and measurement. Here we show that their performance can be further improved by suitably…

Quantum Physics · Physics 2020-09-14 Daniel Basilewitsch , Haidong Yuan , Christiane P. Koch

The optimal control problem for discrete-time systems with colored multiplicative noise is discussed in this paper. The problem will be more difficult to deal with than the case of white noise due to the correlation of the adjoining state.…

Optimization and Control · Mathematics 2019-07-30 Hongdan Li , Juanjuan Xu , Huanshui Zhang

We discuss the disturbance by measurements which unambiguously discriminate between given candidate states. We prove that such an optimal measurement necessarily changes distinguishable states indistinguishable when the inconclusive outcome…

Quantum Physics · Physics 2018-03-14 Ryuitiro Kawakubo , Tatsuhiko Koike

We investigate the optimal tradeoff between information gained about an unknown coherent state and the state disturbance caused by the measurement process. We propose several optical schemes that can enable this task, and we implement one…

Quantum Physics · Physics 2009-11-11 Ulrik L. Andersen , Metin Sabuncu , Radim Filip , Gerd Leuchs

The protection of quantum states is challenging for non-orthogonal states especially in the presence of noises. The recent research breakthrough shows that this difficulty can be overcome by feedback control with weak measurements. However,…

Quantum Physics · Physics 2015-06-16 Y. Yang , X. Y. Zhang , J. Ma , X. X. Yi

Optimal state estimation for linear discrete-time systems is considered. Motivated by the literature on differential privacy, the measurements are assumed to be corrupted by Laplace noise. The optimal least mean square error estimate of the…

Optimization and Control · Mathematics 2016-09-02 Farhad Farokhi , Jezdimir Milosevic , Henrik Sandberg

We study discrimination of m quantum measurements in the scenario when the unknown measurement with n outcomes can be used only once. We show that ancilla-assisted discrimination procedures provide a nontrivial advantage over simple…

Quantum Physics · Physics 2014-12-01 Michal Sedlak , Mario Ziman

We consider the task of multiple parameter estimation in the presence of strong correlated noise with a network of distributed sensors. We study how to find and improve noise-insensitive strategies. We show that sequentially probing GHZ…

Quantum Physics · Physics 2024-07-02 Arne Hamann , Pavel Sekatski , Wolfgang Dür

We investigate a state discrimination problem which interpolates minimum-error and unambiguous discrimination by introducing a margin for the probability of error. We closely analyze discrimination of two pure states with general occurrence…

Quantum Physics · Physics 2015-05-13 H. Sugimoto , T. Hashimoto , M. Horibe , A. Hayashi

We present the results of generalized measurements of optical polarization designed to provide one of three or four distinct outcomes. This has allowed us to discriminate between nonorthogonal polarization states with an error probability…

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

Quantum state discrimination is a fundamental information processing task that serves as a building block for numerous applications and provides implications at the foundational level. In this work, we consider minimum error discrimination…

Quantum Physics · Physics 2026-04-30 Tim Achenbach , Leevi Leppäjärvi , Hanwool Lee , Teiko Heinosaari

We propose and experimentally demonstrate an optimal non-unity gain Gaussian scheme for partial measurement of an unknown coherent state that causes minimal disturbance of the state. The information gain and the state disturbance are…

In this work, we consider optimal state discrimination for a quantum system that interacts with an environment, i.e., states evolve under a quantum channel. We show the conditions on a quantum channel and an ensemble of states such that a…

Quantum Physics · Physics 2019-06-12 Spiros Kechrimparis , Tanmay Singal , Chahan M. Kropf , Joonwoo Bae

We investigate different quantum parameter estimation scenarios in the presence of noise, and identify optimal probe states. For frequency estimation of local Hamiltonians with dephasing noise, we determine optimal probe states for up to 70…

Quantum Physics · Physics 2014-08-10 F. Fröwis , M. Skotiniotis , B. Kraus , W. Dür

We investigate optimal discrimination between two projective quantum measurements on a single qubit. We consider scenario where the measurement that should be identified can be performed twice and we show that adaptive discrimination…

Quantum Physics · Physics 2015-05-14 Jaromir Fiurasek , Michal Micuda

We present an application of particle statistics to the problem of optimal ambiguous discrimination of quantum states. The states to be discriminated are encoded in the internal degrees of freedom of identical particles, and we use the…

Quantum Physics · Physics 2009-11-10 S. Bose , A. Ekert , Y. Omar , N. Paunkovic , V. Vedral