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Quantum state tomography (QST) is the process of reconstructing the complete state of a quantum system (mathematically described as a density matrix) through a series of different measurements. These measurements are performed on a number…

Quantum Physics · Physics 2025-01-08 Hailan Ma , Zhenhong Sun , Daoyi Dong , Dong Gong

Amongst the multitude of state reconstruction techniques, the so-called "quantum tomography" seems to be the most fruitful. In this letter, I will start by developing the mathematical apparatus of quantum tomography and, later, I will…

Quantum Physics · Physics 2007-05-23 M. Paini

We introduce an efficient method to reconstruct the Wigner function of many-mode continuous variable systems. It is based on convex optimization with semidefinite programs, and also includes a version of the maximum entropy principle, in…

Quantum Physics · Physics 2020-02-28 Ludmila A. S. Botelho , Reinaldo O. Vianna

Quantum process tomography (QPT) is a fundamental tool for fully characterizing quantum systems. It relies on querying a set of quantum states as input to the quantum process. Previous QPT methods typically employ a straightforward strategy…

Quantum Physics · Physics 2025-06-06 Jiaqi Yang , Xiaohua Xu , Wei Xie

The tomographic reconstruction of the state of a quantum-mechanical system is an essential component in the development of quantum technologies. We present an overview of different tomographic methods for determining the quantum-mechanical…

Quantum Physics · Physics 2016-02-09 Roman Schmied

Variational quantum algorithms exploit the features of superposition and entanglement to optimize a cost function efficiently by manipulating the quantum states. They are suitable for noisy intermediate-scale quantum (NISQ) computers that…

Quantum Physics · Physics 2023-08-29 Yunya Liu , Jiakun Liu , Jordan R. Raney , Pai Wang

The impressive pace of advance of quantum technology calls for robust and scalable techniques for the characterization and validation of quantum hardware. Quantum process tomography, the reconstruction of an unknown quantum channel from…

Objective: Despite recent advancements in quantum computing, the limited number of available qubits has hindered progress in CT reconstruction. This study investigates the feasibility of utilizing quantum annealing-based computed tomography…

Quantum Physics · Physics 2024-02-12 Akihiro Haga

Quantum state tomography is the standard tool in current experiments for verifying that a state prepared in the lab is close to an ideal target state, but up to now there were no rigorous methods for evaluating the precision of the state…

Quantum Physics · Physics 2018-10-04 Takanori Sugiyama , Peter S. Turner , Mio Murao

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), the process through which the density matrix of a quantum system is characterized from measurements of specific observables, is a fundamental pillar in the fields of quantum information and computation. In…

Quantum Physics · Physics 2024-01-30 J. L. Montenegro Ferreira , B. de Lima Bernardo

Coherent-state quantum process tomography (csQPT) is a method of completely characterizing a quantum-optical "black box" by probing it with coherent states and performing homodyne measurements on the output [M. Lobino et al, Science 322,…

Quantum Physics · Physics 2013-03-15 Aamir Anis , A. I. Lvovsky

We describe algorithms to obtain an approximate classical description of a $d$-dimensional quantum state when given access to a unitary (and its inverse) that prepares it. For pure states we characterize the query complexity for…

Quantum Physics · Physics 2022-07-19 Joran van Apeldoorn , Arjan Cornelissen , András Gilyén , Giacomo Nannicini

Quantum state tomography, which aims to find the best description of a quantum state -- the density matrix, is an essential building block in quantum computation and communication. Standard techniques for state tomography are incapable of…

Quantum Physics · Physics 2022-11-18 Markus Rambach , Akram Youssry , Marco Tomamichel , Jacquiline Romero

We revisit quantum tomography in an informationally incomplete scenario and propose improved state reconstruction methods using deep neural networks. In the first approach, the trained network predicts an optimal linear or quadratic…

Quantum Physics · Physics 2026-01-21 Mateusz Krawczyk , Pavel Baláž , Katarzyna Roszak , Jarosław Pawłowski

We present a novel quantum tomographic reconstruction method based on Bayesian inference via the Kalman filter update equations. The method not only yields the maximum likelihood/optimal Bayesian reconstruction, but also a covariance matrix…

Quantum Physics · Physics 2011-05-13 Koenraad M. R. Audenaert , S. Scheel

Learning-based 3D reconstruction models, represented by Visual Geometry Grounded Transformers (VGGTs), have made remarkable progress with the use of large-scale transformers. Their prohibitive computational and memory costs severely hinder…

Computer Vision and Pattern Recognition · Computer Science 2026-03-10 Weilun Feng , Haotong Qin , Mingqiang Wu , Chuanguang Yang , Yuqi Li , Xiangqi Li , Zhulin An , Libo Huang , Yulun Zhang , Michele Magno , Yongjun Xu

We propose a high efficiency tomographic scheme to reconstruct an unknown quantum state of the qubits by using a series of quantum nondemolition (QND) measurements. The proposed QND measurements of the qubits are implemented by probing the…

Quantum Physics · Physics 2015-05-20 J. S. Huang , L. F. Wei , C. H. Oh

There exists, in general, a convex set of quantum state estimators that maximize the likelihood for informationally incomplete data. We propose an estimation scheme, catered to measurement data of this kind, to search for the exact…

Quantum state tomography, an important task in quantum information processing, aims at reconstructing a state from prepared measurement data. Bayesian methods are recognized to be one of the good and reliable choice in estimating quantum…

Statistics Theory · Mathematics 2017-06-15 The Tien Mai , Pierre Alquier