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Related papers: Quantum-enhanced tomography of unitary processes

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Quantum computing can provide speedups in solving many problems as the evolution of a quantum system is described by a unitary operator in an exponentially large Hilbert space. Such unitary operators change the phase of their eigenstates…

Quantum Physics · Physics 2024-01-23 Youle Wang , Lei Zhang , Zhan Yu , Xin Wang

Characterizing complex quantum systems is a vital task in quantum information science. Quantum tomography, the standard tool used for this purpose, uses a well-designed measurement record to reconstruct quantum states and processes. It is,…

Quantum Physics · Physics 2015-12-10 Amir Kalev , Robert L. Kosut , Ivan H. Deutsch

Alternatively to the full reconstruction of an unknown quantum process, the so-called selective and efficient quantum process tomography (SEQPT) allows estimating, individually and up to the required accuracy, a given element of the matrix…

Quantum Physics · Physics 2023-01-27 Quimey Pears Stefano , Ignacio Perito , Lorena Rebón

Quantum information processing provides remarkable advantages over its classical counterpart. Quantum optical systems are proved to be sufficient for realizing general quantum tasks, which however often rely on single photon sources. In…

Quantum Physics · Physics 2016-12-08 Xiao Yuan , Zhen Zhang , Norbert Lutkenhaus , Xiongfeng Ma

We propose an estimation method for quantum measurement tomography (QMT) based on semidefinite programming (SDP), and discuss how it may be employed to detect experimental imperfections, such as shot noise and/or faulty preparation of the…

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

Quantum process tomography is a useful tool for characterizing quantum processes. This task is essential for the development of different areas, such as quantum information processing. In this work, we present a protocol for selective…

Quantum Physics · Physics 2025-04-22 Virginia Feldman , Ariel Bendersky

Quantum process tomography (QPT) is crucial for advancing quantum technologies, including quantum computers, quantum networks and quantum sensors. Shadow process tomography (SPT) utilizes the Choi isomorphism to map QPT to shadow state…

Quantum Physics · Physics 2025-07-16 Haigang Wang , Kan He

We describe an approach for characterizing the process of quantum gates using quantum process tomography, by first modeling them in an extended Hilbert space, which includes non-qubit degrees of freedom. To prevent unphysical processes from…

Quantum Physics · Physics 2008-11-26 Peter P. Rohde , G. J. Pryde , J. L. O'Brien , Timothy C. Ralph

Quantum sensing with undetected photons is a technique where photons of one wavelength probe a sample, but information is extracted by measuring photons of another wavelength that never interacts with the sample. This has seen significant…

We present an example of quantum process tomography performed on a single solid state qubit. The qubit used is two energy levels of the triplet state in the Nitrogen-Vacancy defect in Diamond. Quantum process tomography is applied to a…

Quantum Physics · Physics 2007-05-23 M. Howard , J. Twamley , C. Wittmann , T. Gaebel , F. Jelezko , J. Wrachtrup

Accurately estimating the overlap between quantum states is a fundamental task in quantum information processing. While various strategies using distinct quantum measurements have been proposed for overlap estimation, the lack of…

Quantum Physics · Physics 2025-02-13 Hao Zhan , Ben Wang , Minghao Mi , Jie Xie , Liang Xu , Aonan Zhang , Lijian Zhang

Quantum process tomography (QPT) is a fundamental task to characterize the dynamics of quantum systems. In contrast to standard QPT, ancilla-assisted process tomography (AAPT) framework introduces an extra ancilla system such that a single…

Quantum Physics · Physics 2023-11-01 Shuixin Xiao , Yuanlong Wang , Daoyi Dong , Jun Zhang

Characterization of quantum dynamics is a fundamental problem in quantum physics and quantum information science. Several methods are known which achieve this goal, namely Standard Quantum Process Tomography (SQPT), Ancilla-Assisted Process…

Quantum Physics · Physics 2008-03-19 M. Mohseni , A. T. Rezakhani , D. A. Lidar

High-dimensional quantum information processing has become a mature field of research with several different approaches being adopted for the encoding of $D$-dimensional quantum systems. Such progress has fueled the search of reliable…

Quantum Physics · Physics 2019-01-30 D. Martínez , M. A. Solís-Prosser , G. Cañas , O. Jiménez , A. Delgado , G. Lima

Path-entangled multi-photon states allow optical phase-sensing beyond the shot-noise limit, provided that an efficient parity measurement can be implemented. Realising this experimentally is technologically demanding, as it requires…

Quantum state tomography (QST) for reconstructing pure states requires exponentially increasing resources and measurements with the number of qubits by using state-of-the-art quantum compressive sensing (CS) methods. In this article, QST…

Quantum Physics · Physics 2021-11-16 Burhan Gulbahar

Quantum Metrology is one of the most promising application of quantum technologies. The aim of this research field is the estimation of unknown parameters exploiting quantum resources, whose application can lead to enhanced performances…

Quantum Physics · Physics 2020-03-13 Emanuele Polino , Mauro Valeri , Nicolò Spagnolo , Fabio Sciarrino

The characterization of quantum dynamics is a fundamental and central task in quantum mechanics. This task is typically addressed by quantum process tomography (QPT). Here we present an alternative "direct characterization of quantum…

Quantum Physics · Physics 2007-05-23 M. Mohseni , D. A. Lidar

We present a quantum-analogous experimental demonstration of variational quantum process tomography using an optical processor. This approach leverages classical one-hot encoding and unitary decomposition to perform the variational quantum…

Quantum Physics · Physics 2025-07-14 Vladlen Galetsky , Paul Kohl , Janis Nötzel
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