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Related papers: A generalized unknown qubit discriminator

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We propose a quantum device that can approximate any projective measurement on a qubit. The desired measurement basis is selected by the quantum state of a "program register". The device is optimized with respect to maximal average fidelity…

Quantum Physics · Physics 2009-11-07 Jaromir Fiurasek , Miloslav Dusek , Radim Filip

We derive general discrimination of quantum states chosen from a certain set, given initial $M$ copies of each state, and obtain the matrix inequality, which describe the bound between the maximum probability of correctly determining and…

Quantum Physics · Physics 2009-10-31 Chuan-Wei Zhang , Chuan-Feng Li , Guang-Can Guo

We study possible realizations of generalized quantum measurements on measurement-assisted programmable quantum processors. We focus our attention on the realization of von Neumann measurements and informationally complete POVMs. It is…

Quantum Physics · Physics 2016-09-08 Mario Ziman , Vladimir Buzek

It is a crucial feature of quantum mechanics that not all measurements are compatible with each other. However, if measurements suffer from noise they may lose their incompatibility. Here, we consider the effect of white noise and determine…

Quantum Physics · Physics 2026-01-30 Martin J. Renner

Two unknown states can be unambiguously distinguished by a universal programmable discriminator, which has been widely discussed in previous works and the optimal solution has also been obtained. In this paper, we investigate the…

Quantum Physics · Physics 2016-10-11 Xiaobing Sunian , Yuwei Li , Tao Zhou

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

Quantum computing is a growing field where the information is processed by two-levels quantum states known as qubits. Current physical realizations of qubits require a careful calibration, composed by different experiments, due to noise and…

Quantum Physics · Physics 2023-09-15 Edoardo Pedicillo , Andrea Pasquale , Stefano Carrazza

We address the problem of unambiguously identifying the state of a probe qudit with the state of one of d reference qudits. The reference states are assumed pure and linearly independent but we have no knowledge of them. The state of the…

Quantum Physics · Physics 2009-11-13 Ulrike Herzog , Janos A. Bergou

We initially consider a quantum system consisting of two qubits, which can be in one of two nonorthogonal states, \Psi_0 or \Psi_1. We distribute the qubits to two parties, Alice and Bob. They each measure their qubit and then compare their…

Quantum Physics · Physics 2009-11-11 Jihane Mimih , Mark Hillery

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

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

A method to compute the optimal success probability of discrimination of N arbitrary quantum states is presented, based on the decomposition of any N-outcome measurement into sequences of nested two-outcome ones. In this way the…

Quantum Physics · Physics 2017-04-12 Matteo Rosati , Giacomo De Palma , Andrea Mari , Vittorio Giovannetti

We consider the problem of designing a measurement to minimize the probability of a detection error when distinguishing between a collection of possibly non-orthogonal mixed quantum states. We show that if the quantum state ensemble…

Quantum Physics · Physics 2009-11-10 Yonina C. Eldar

In this paper we consider the problem of unambiguous discrimination between a set of linearly independent pure quantum states. We show that the design of the optimal measurement that minimizes the probability of an inconclusive result can…

Quantum Physics · Physics 2016-11-17 Yonina C. Eldar

The optimal discrimination of non-orthogonal quantum states with minimum error probability is a fundamental task in quantum measurement theory as well as an important primitive in optical communication. In this work, we propose and…

Quantum Physics · Physics 2009-11-13 C. Wittmann , M. Takeoka , K. N. Cassemiro , M. Sasaki , G. Leuchs , U. L. Andersen

In this paper we present the solution to the problem of optimally discriminating among quantum states, i.e., identifying the states with maximum probability of success when a certain fixed rate of inconclusive answers is allowed. By varying…

Quantum Physics · Physics 2013-05-31 E. Bagan , R. Munoz-Tapia , G. A. Olivares-Renteria , J. A. Bergou

The distinguishability between two quantum states can be defined in terms of their trace distance. The operational meaning of this definition involves a maximization over measurement projectors. Here we introduce an alternative definition…

Quantum Physics · Physics 2024-09-04 Adrian A. Budini , Ruynet L. de Matos Filho , Marcelo F. Santos

We propose quantum devices that can realize probabilistically different projective measurements on a qubit. The desired measurement basis is selected by the quantum state of a program register. First we analyze the phase-covariant…

Quantum Physics · Physics 2009-11-10 Jaromir Fiurasek , Miloslav Dusek

Using the necessary and sufficient conditions, minimum error discrimination among two sets of similarity transformed equiprobable quantum qudit states is investigated. In the case that the unitary operators are generating sets of two…

Quantum Physics · Physics 2016-11-25 M. A. Jafarizadeh , Y. Mazhari Khiavi , Y. Akbari Kourbolagh

The problem of discriminating with minimum error between two mixed quantum states is reviewed, with emphasize on the detection operators necessary for performing the measurement. An analytical result is derived for the minimum probability…

Quantum Physics · Physics 2009-11-10 Ulrike Herzog