English
Related papers

Related papers: Direct Fidelity Estimation for Generic Quantum Sta…

200 papers

Recently quantum tomography has been proposed as a fundamental tool for prototyping a few qubit quantum device. It allows the complete reconstruction of the state produced from a given input into the device. From this reconstructed density…

Quantum Physics · Physics 2009-11-07 R. T. Thew , K. Nemoto , A. G. White , W. J. Munro

High-fidelity quantum state transfer is critical for quantum communication and scalable quantum computation. Current quantum state transfer algorithms on the complete bipartite graph, which are based on discrete-time quantum walk search…

Quantum Physics · Physics 2023-02-24 Dan Li , Jia-Ni Huang , Yu-Qian Zhou , Yu-Guang Yang

Quantum information systems are on a path to vastly exceed the complexity of any classical device. The number of entangled qubits in quantum devices is rapidly increasing and the information required to fully describe these systems scales…

We present a two-step exact remote state preparation protocol of an arbitrary qubit with the aid of a three-particle Greenberger-Horne-Zeilinger state. Generalization of this protocol for higher-dimensional Hilbert space systems among three…

Quantum Physics · Physics 2015-05-13 Meiyu Wang , Fengli Yan

Quantum state tomography is a powerful, but resource-intensive, general solution for numerous quantum information processing tasks. This motivates the design of robust tomography procedures that use relevant resources as sparingly as…

Quantum Physics · Physics 2022-01-17 Fernando G. S. L. Brandão , Richard Kueng , Daniel Stilck França

It has been known that all bipartite pure quantum states can be certified by quantum self-testing, i.e., any such states can be pinned down completely based on the statistics produced by local quantum measurements. A notable feature of…

Quantum Physics · Physics 2024-12-13 Lijinzhi Lin , Zhenyu Chen , Xiaodie Lin , Zhaohui Wei

To certify that an experimentally implemented quantum transformation is a certain unitary operation U on a d-dimensional Hilbert space, it suffices to determine fidelities of output states for d+1 suitably chosen pure input states [Reich et…

Quantum Physics · Physics 2014-01-24 Jaromir Fiurasek , Michal Sedlak

Quantum phase estimation is one of the key algorithms in the field of quantum computing, but up until now, only approximate expressions have been derived for the probability of error. We revisit these derivations, and find that by ensuring…

Quantum Physics · Physics 2012-02-13 James M. Chappell , Max A. Lohe , Lorenz von Smekal , Azhar Iqbal , Derek Abbott

We use a meta-learning neural-network approach to analyse data from a measured quantum state. Once our neural network has been trained it can be used to efficiently sample measurements of the state in measurement bases not contained in the…

Quantum Physics · Physics 2021-07-01 Alistair W. R. Smith , Johnnie Gray , M. S. Kim

Quantum error correction and quantum error detection necessitate syndrome measurements to detect errors. Performing syndrome measurements for each stabilizer generator can be a significant overhead, considering the fact that the readout…

Quantum Physics · Physics 2023-10-31 Kento Tsubouchi , Yasunari Suzuki , Yuuki Tokunaga , Nobuyuki Yoshioka , Suguru Endo

Quantum state tomography (QST) is the process of reconstructing the state of a quantum system (mathematically described as a density matrix) through a series of different measurements, which can be solved by learning a parameterized…

Quantum Physics · Physics 2025-03-31 Hailan Ma , Zhenhong Sun , Daoyi Dong , Chunlin Chen , Herschel Rabitz

Quantum tomography is a widely applicable tool for complete characterization of quantum states and processes. In the present work, we develop a method for precision-guaranteed quantum process tomography. With the use of the…

Quantum Physics · Physics 2020-01-17 E. O. Kiktenko , D. N. Kublikova , A. K. Fedorov

Simulating time evolution is one of the most natural applications of quantum computers and is thus one of the most promising prospects for achieving practical quantum advantage. Here, we develop quantum algorithms to extract thermodynamic…

Quantum Physics · Physics 2026-03-10 Matthew L. Goh , Bálint Koczor

Producing quantum states at random has become increasingly important in modern quantum science, with applications both theoretical and practical. In particular, ensembles of such randomly-distributed, but pure, quantum states underly our…

We provide a new quantum algorithm that efficiently determines the quality of a least-squares fit over an exponentially large data set by building upon an algorithm for solving systems of linear equations efficiently (Harrow et al., Phys.…

Quantum Physics · Physics 2013-01-10 Nathan Wiebe , Daniel Braun , Seth Lloyd

Quantum teleportation with an arbitrary two-qubit state can be appropriately characterized in terms of maximal fidelity and fidelity deviation. The former quantifies optimality of the process and is defined as the maximal average fidelity…

Quantum Physics · Physics 2020-03-23 Arkaprabha Ghosal , Debarshi Das , Saptarshi Roy , Somshubhro Bandyopadhyay

Quantum teleportation is one of the essential primitives of quantum communication. We suggest that any quantum teleportation scheme can be characterized by its efficiency, i.e. how often it succeeds to teleport, its fidelity, i.e. how well…

Quantum Physics · Physics 2015-06-26 Dik Bouwmeester , Jian-Wei Pan , Harald Weinfurter , Anton Zeilinger

We propose a practical, scalable, and efficient scheme for quantum computation using spatially separated matter qubits and single photon interference effects. The qubit systems can be NV-centers in diamond, Pauli-blockade quantum dots with…

Quantum Physics · Physics 2009-11-10 Sean D. Barrett , Pieter Kok

We present a novel protocol for high-fidelity qubit state preparation and measurement (SPAM) that combines standard SPAM methods with a series of in-sequence measurements to detect and remove errors. The protocol can be applied in any…

Entanglement lies at the heart of quantum information science, serving as a key resource for quantum communication, computation, and metrology. Consequently, high-precision entangled state preparation and efficient verification are…