English
Related papers

Related papers: Optimal estimation of qubit states with continuous…

200 papers

A new qubit tomography protocol is introduced, based on a continuous positive operator valued measure, which is supported by the set of pure states, and equivariant under the symmetry group SO(3,R) of the qubit state space. Thus the sample…

Quantum Physics · Physics 2008-03-14 Tamás Tasnádi

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

This paper establishes a nearly optimal algorithm for estimating the frequencies and amplitudes of a mixture of sinusoids from noisy equispaced samples. We derive our algorithm by viewing line spectral estimation as a sparse recovery…

Information Theory · Computer Science 2013-04-02 Gongguo Tang , Badri Narayan Bhaskar , Benjamin Recht

Efficient and accurate state estimation is essential for the optimal management of the future smart grid. However, to meet the requirements of deploying the future grid at a large scale, the state estimation algorithm must be able to…

Information Theory · Computer Science 2017-09-29 Jung-Chieh Chen , Hwei-Ming Chung , Chao-Kai Wen , Wen-Tai Li , Jen-Hao Teng

Quantum estimation involving multiple parameters remains an important problem of both theoretical and practical interest. In this work, we study the problem of simultaneous estimation of two parameters that are respectively associate with…

Quantum Physics · Physics 2022-03-25 Yink Loong Len

As quantum systems expand in size and complexity, manual qubit characterization and gate optimization will be a non-scalable and time-consuming venture. Physical qubits have to be carefully calibrated because quantum processors are very…

Quantum Physics · Physics 2022-05-26 Peng Qian , Shahid Qamar , Xiao Xiao , Yanwu Gu , Xudan Chai , Zhen Zhao , Nicolo Forcellini , Dong E. Liu

The measurement of a quantum two-level system, or a qubit in modern terminology, often involves an electromagnetic field that interacts with the qubit, before the field is measured continuously and the qubit state is inferred from the noisy…

Quantum Physics · Physics 2014-08-27 Shilin Ng , Mankei Tsang

Quantum state discrimination involves identifying a given state out of a set of possible states. When the states are mutually orthogonal, perfect state discrimination is always possible using a global measurement. In the case of…

Quantum Physics · Physics 2023-09-13 Scott M. Cohen

We consider the problem of a state determination for a two-level quantum system which can be in one of two nonorthogonal mixed states. It is proved that for the two independent identical systems the optimal combined measurement (which…

Quantum Physics · Physics 2007-05-23 A. E. Allahverdyan , D. B. Saakian

We address estimation of one-parameter unitary gates for qubit systems and seek for optimal probes and measurements. Single- and two-qubit probes are analyzed in details focusing on precision and stability of the estimation procedure.…

Quantum Physics · Physics 2009-11-13 Berihu Teklu , Stefano Olivares , Matteo G A Paris

In the context of a large system of $N$ neurons interacting through spike events in a mean-field regime as $N\rightarrow \infty$, we characterize the estimation of a multidimensional parameter in the spiking rate, when the neural states are…

Statistics Theory · Mathematics 2026-05-06 Aline Duarte , Dasha Loukianova , Aurélien Velleret

Quantum state estimation is important for various quantum information processes, including quantum communications, computation, and metrology, which require the characterization of quantum states for evaluation and optimization. We present…

Quantum Physics · Physics 2026-04-15 C. Vargas , L. Pereira , A. Delgado

Consider the task of verifying that a given quantum device, designed to produce a particular entangled state, does indeed produce that state. One natural approach would be to characterise the output state by quantum state tomography; or…

Quantum Physics · Physics 2018-04-26 Sam Pallister , Noah Linden , Ashley Montanaro

We investigate the problem of optimally approximating a desired state by the convex mixing of a set of available states. The problem is recasted as finding the optimal state with the minimum distance from target state in a convex set of…

Quantum Physics · Physics 2022-11-23 Huaqi Zhou , Ting Gao , Fengli Yan

We study an optimum measurement for quantum state discrimination, which maximizes the probability of correct results when the probability of inconclusive results is fixed at a given value. The measurement describes minimum-error…

Quantum Physics · Physics 2012-09-26 Ulrike Herzog

The optimal state determination (or tomography) is studied for a composite system of two qubits when measurements can be performed on one of the qubits and interactions of the two qubits can be implemented. The goal is to minimize the…

Quantum Physics · Physics 2009-11-13 D. Petz , K. M. Hangos , A. Szanto , F. Szollosi

We show a geometric formulation for minimum-error discrimination of qubit states, that can be applied to arbitrary sets of qubit states given with arbitrary a priori probabilities. In particular, when qubit states are given with equal…

Quantum Physics · Physics 2015-06-04 Joonwoo Bae , Won-Young Hwang

This dissertation studies the statistics and modeling of a quantum system probed by a coherent laser field. We focus on an ensemble of qubits dispersively coupled to a traveling wave light field. The first research topic explores the…

Quantum Physics · Physics 2013-01-29 Robert L. Cook

Optimal strategies for local quantum metrology -- including the preparation of optimal probe states, implementation of optimal control and measurement strategies, are well established. However, for distributed quantum metrology, where the…

Quantum Physics · Physics 2025-09-29 Zhiyao Hu , Allen Zang , Jianwei Wang , Tian Zhong , Haidong Yuan , Liang Jiang , Zain H. Saleem

In this paper, we explore an efficient online algorithm for quantum state estimation based on a matrix-exponentiated gradient method previously used in the context of machine learning. The state update is governed by a learning rate that…

Quantum Physics · Physics 2019-03-28 Akram Youssry , Christopher Ferrie , Marco Tomamichel