English
Related papers

Related papers: Maximum-Likelihood Quantum State Tomography by Sof…

200 papers

In maximum-likelihood quantum state tomography, both the sample size and dimension grow exponentially with the number of qubits. It is therefore desirable to develop a stochastic first-order method, just like stochastic gradient descent for…

Quantum Physics · Physics 2022-11-24 Chung-En Tsai , Hao-Chung Cheng , Yen-Huan Li

We propose an iterative algorithm that computes the maximum-likelihood estimate in quantum state tomography. The optimization error of the algorithm converges to zero at an $O ( ( 1 / k ) \log D )$ rate, where $k$ denotes the number of…

Quantum Physics · Physics 2021-10-05 Chien-Ming Lin , Hao-Chung Cheng , Yen-Huan Li

Quantum state tomography (QST) is typically performed from a frequentist viewpoint using maximum likelihood estimation (MLE) which seeks to find the best plausible state consistent with the data by maximizing a likelihood function /…

Quantum Physics · Physics 2022-12-22 Daniel J. Lum , Yaakov Weinstein

We introduce the concept of selective quantum state tomography or SQST, a tomographic scheme that enables a user to estimate arbitrary elements of an unknown quantum state using a fixed measurement record. We demonstrate how this may be…

Quantum Physics · Physics 2020-06-12 Joshua Morris , Borivoje Dakić

Quantum State Tomography is the task of determining an unknown quantum state by making measurements on identical copies of the state. Current algorithms are costly both on the experimental front -- requiring vast numbers of measurements --…

Quantum Physics · Physics 2018-12-18 Yihui Quek , Stanislav Fort , Hui Khoon Ng

Quantum State Tomography (QST) is a fundamental technique in Quantum Information Processing (QIP) for reconstructing unknown quantum states. However, the conventional QST methods are limited by the number of measurements required, which…

Quantum tomography requires repeated measurements of many copies of the physical system, all prepared by a source in the unknown state. In the limit of very many copies measured, the often-used maximum-likelihood (ML) method for converting…

Quantum Physics · Physics 2014-10-09 Hui Khoon Ng , Berthold-Georg Englert

Consider the problem of minimizing an expected logarithmic loss over either the probability simplex or the set of quantum density matrices. This problem includes tasks such as solving the Poisson inverse problem, computing the…

Optimization and Control · Mathematics 2024-03-12 Chung-En Tsai , Hao-Chung Cheng , Yen-Huan Li

Existing quantum state tomography methods are limited in scalability due to their high computation and memory demands, making them impractical for recovery of large quantum states. In this work, we address these limitations by reformulating…

Quantum Physics · Physics 2025-10-21 Kuchibhotla Aditi , Stephen Becker

Quantum state tomography (QST) is one of the fundamental problems in quantum information. Among various metrics, sample complexity is widely used to evaluate QST algorithms. While multi-copy measurements are known to achieve optimal sample…

Quantum Physics · Physics 2025-09-17 Gyungmin Cho , Dohun Kim

We initiate the study of online quantum state tomography (QST), where the matrix representation of an unknown quantum state is reconstructed by sequentially performing a batch of measurements and updating the state estimate using only the…

Quantum Physics · Physics 2025-07-11 Jian-Feng Cai , Yuling Jiao , Yinan Li , Xiliang Lu , Jerry Zhijian Yang , Juntao You

Maximum likelihood estimation is one of the most used methods in quantum state tomography, where the aim is to reconstruct the density matrix of a physical system from measurement results. One strategy to deal with positivity and unit trace…

With the capability to find the best fit to arbitrarily complicated data patterns, machine-learning (ML) enhanced quantum state tomography (QST) has demonstrated its advantages in extracting complete information about the quantum states.…

Quantum Physics · Physics 2022-03-31 Hsien-Yi Hsieh , Jingyu Ning , Yi-Ru Chen , Hsun-Chung Wu , Hua Li Chen , Chien-Ming Wu , Ray-Kuang Lee

Tomography of a quantum state is usually based on positive operator-valued measure (POVM) and on their experimental statistics. Among the available reconstructions, the maximum-likelihood (MaxLike) technique is an efficient one. We propose…

Conventional methods for computing maximum-likelihood estimators (MLE) often converge slowly in practical situations, leading to a search for simplifying methods that rely on additional assumptions for their validity. In this work, we…

Quantum Physics · Physics 2017-06-28 Jiangwei Shang , Zhengyun Zhang , Hui Khoon Ng

In quantum state tomography, the estimated frequencies do not correspond directly to a physical quantum state, due to statistical fluctuations. Thus, one resorts to point estimators that return the state that matches observations the best,…

Quantum Physics · Physics 2018-11-09 Sacha Schwarz , Bruno Eckmann , Denis Rosset , André Stefanov

A simple yet efficient method of linear regression estimation (LRE) is presented for quantum state tomography. In this method, quantum state reconstruction is converted into a parameter estimation problem of a linear regression model and…

Quantum Physics · Physics 2013-12-18 Bo Qi , Zhibo Hou , Li Li , Daoyi Dong , Guoyong Xiang , Guangcan Guo

Quantum state tomography (QST) aiming at reconstructing the density matrix of a quantum state plays an important role in various emerging quantum technologies. Recognizing the challenges posed by imperfect measurement data, we develop a…

Quantum Physics · Physics 2025-03-31 Hailan Ma , Daoyi Dong , Ian R. Petersen , Chang-Jiang Huang , Guo-Yong Xiang

Precise reconstruction of unknown quantum states from measurement data, a process commonly called quantum state tomography, is a crucial component in the development of quantum information processing technologies. Many different tomography…

Quantum Physics · Physics 2022-10-28 Ingrid Strandberg

Quantum state tomography (QST) is a fundamental task in quantum information science that aims to reconstruct unknown quantum states from measurement data. However, the exponential growth of Hilbert-space dimension with system size makes…

Quantum Physics · Physics 2026-05-27 Zhen Qin , Michael B. Wakin , Zhihui Zhu
‹ Prev 1 2 3 10 Next ›