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Related papers: Quantum-enhanced tomography of unitary processes

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Quantum process tomography (QPT), used to estimate the linear map that best describes a quantum operation, is usually performed using a priori assumptions about state preparation and measurement (SPAM), which yield a biased and inconsistent…

Quantum Physics · Physics 2025-03-14 Robin Blume-Kohout , Kenneth Rudinger , Timothy Proctor

Quantum tomography is a fundamental technique for characterizing, benchmarking, and verifying quantum states and devices. It plays a crucial role in advancing quantum technologies and deepening our understanding of quantum mechanics.…

Quantum state tomography (QST) is the gold standard technique for obtaining an estimate for the state of small quantum systems in the laboratory. Its application to systems with more than a few constituents (e.g. particles) soon becomes…

We review single-qubit quantum process tomography for trace-preserving and nontrace-preserving processes, and derive explicit forms of the general constraints for fitting experimental data. These forms provide additional insight into the…

Quantum Physics · Physics 2015-02-05 Ramesh Bhandari , Nicholas A. Peters

Using coherent states in optical quantum process tomography is a practically-relevant approach. Here, we develop a framework for complete characterization of quantum-optical processes in terms of normally-ordered moments by using coherent…

Quantum Physics · Physics 2017-04-11 M. Ghalaii , A. T. Rezakhani

We use hyperentangled photons to experimentally implement an entanglement-assisted quantum process tomography technique known as Direct Characterization of Quantum Dynamics. Specifically, hyperentanglement-assisted Bell-state analysis…

Quantum Physics · Physics 2014-08-12 Trent M. Graham , Julio T. Barreiro , Masoud Mohseni , Paul G. Kwiat

Quantum process tomography has become increasingly critical as the need grows for robust verification and validation of candidate quantum processors. Here, we present an approach for efficient quantum process tomography that uses a…

Quantum Physics · Physics 2020-03-25 L. C. G. Govia , G. J. Ribeill , D. Ristè , M. Ware , H. Krovi

Determining an unknown quantum state from an ensemble of identical systems is a fundamental, yet experimentally demanding, task in quantum science. Here we study the number of measurement bases needed to fully characterize an arbitrary…

Quantum Physics · Physics 2019-02-11 Leonardo Banchi , W. Steven Kolthammer , M. S. Kim

Quantum state tomography is a central technique for the characterization and verification of quantum systems. Standard tomography is widely used for low-dimensional systems, but for larger systems, it becomes impractical due to the…

Debugging quantum states transformations is an important task of modern quantum computing. The use of quantum tomography for these purposes significantly expands the range of possibilities. However, the presence of preparation and…

Quantum Physics · Physics 2022-01-11 B. I. Bantysh , Yu. I. Bogdanov

We develop a practical quantum tomography protocol and implement measurements of pure states of ququarts realized with polarization states of photon pairs (biphotons). The method is based on an optimal choice of the measuring scheme's…

Quantum Physics · Physics 2008-11-17 E. V. Moreva , Yu. I. Bogdanov , A. K. Gavrichenko , S. P. Kulik , I. Tikhonov

Quantum process tomography is a procedure by which the unknown dynamical evolution of an open quantum system can be fully experimentally characterized. We demonstrate explicitly how this procedure can be implemented with a nuclear magnetic…

Quantum Physics · Physics 2007-05-23 Andrew M. Childs , Isaac L. Chuang , Debbie W. Leung

The description of excited state dynamics in multichromophoric systems constitutes both a theoretical and experimental challenge in modern physical chemistry. An experimental protocol which can systematically characterize both coherent and…

Quantum Physics · Physics 2011-10-31 Joel Yuen-Zhou , Jacob J. Krich , Masoud Mohseni , Alán Aspuru-Guzik

Long-lived electronic coherences in various photosynthetic complexes at cryogenic and room temperature have generated vigorous efforts both in theory and experiment to understand their origins and explore their potential role to biological…

Quantum Physics · Physics 2010-12-16 Patrick Rebentrost , Sangwoo Shim , Joel Yuen-Zhou , Alán Aspuru-Guzik

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

Quantum sensing exploits quantum phenomena to enhance the detection and estimation of classical parameters of physical systems and biological entities, particularly so as to overcome the inefficiencies of its classical counterparts. A…

Quantum processes involving single-photon states are of broad interest in particular for quantum communication. Extending to continuous values a recent proposal by Yuan et al \cite{YUAN16}, we show that single-photon quantum processes can…

Quantum Physics · Physics 2017-05-24 P. Valente , A. Lezama

Recent advances in quantum computers and simulators are steadily leading us towards full-scale quantum computing devices. Due to the fact that debugging is necessary to create any computing device, quantum tomography (QT) is a critical…

Quantum Physics · Physics 2021-10-12 B. I. Bantysh , A. Yu. Chernyavskiy , Yu. I. Bogdanov

Conditional quantum optical processes enable a wide range of technologies from generation of highly non-classical states to implementation of quantum logic operations. The process fidelity that can be achieved in a realistic implementation…

Quantum Physics · Physics 2015-06-23 Merlin Cooper , Eirion Slade , Michal Karpinski , Brian J. Smith

A photon is the single excitation of a particular spatiotemporal mode of the electromagnetic field. A precise knowledge of the mode structure is therefore essential for its processing and detection, as well as for applying generic quantum…