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Related papers: Decoherence in a quantum neural network

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The decoherence of mixed electron-nuclear spin qubits is a topic of great current importance, but understanding is still lacking: while important decoherence mechanisms for spin qubits arise from quantum spin bath environments with slow…

Mesoscale and Nanoscale Physics · Physics 2015-05-26 S. J. Balian , Gary Wolfowicz , John J. L. Morton , T. S. Monteiro

Molecular spins offer promise in emerging quantum technologies such as quantum sensing and computing. At low temperatures, nuclear spin-spin interactions affect electron spin coherence lifetimes through pure dephasing. Nuclear-spin noise…

Quantum Physics · Physics 2026-05-06 Timothy J. Krogmeier , James Bradley , Anthony W. Schlimgen , Kade Head-Marsden

Coherent states offer a promising path for near-term quantum computing due to their inherent protection against bit-flip noise. However, their large photon numbers can be challenging for numerical simulation. This paper introduces an…

Predicting the quantum dynamics of promising solid-state and molecular quantum technology candidates remains a formidable challenge. Yet, accessing these dynamics is key to understanding and controlling decoherence mechanisms -- a…

Chemical Physics · Physics 2026-04-10 Tianchu Li , Pranay Venkatesh , Nanako Shitara , Andrés Montoya-Castillo

We study the decoherence of a quantum computer in an environment which is inherently correlated in time and space. We first derive the nonunitary time evolution of the computer and environment in the presence of a stabilizer error…

Quantum Physics · Physics 2007-05-23 E. Novais , Harold U. Baranger

We propose and solve a simple but very general quantum model of an SU(2) spin interacting with a large external system with N states. The coupling is described by a random hamiltonian in a new general gaussian SU(2)xU(N) random matrix…

Mathematical Physics · Physics 2011-01-13 Francois David

Multiple quantum (MQ) NMR methods \cite{Baum} are applied to the analysis of various problems of quantum information processing. It is shown that the two-spin/two-quantum Hamiltonian \cite{Baum} describing MQ NMR dynamics is related to the…

Quantum Physics · Physics 2017-01-16 G. A. Bochkin , S. I. Doronin , S. G. Vasil'ev , A. V. Fedorova , E. B. Fel'dman

In this report, we examine the decoherence of a spin qubits system coupled to counted spin chain with a $1/r^2$ interaction by using influence functional. We also examine the time evolution of density matrix numerically when environment is…

Mesoscale and Nanoscale Physics · Physics 2008-12-20 Toshifumi Itakura

Maintaining coherence of a qubit is of vital importance for realizing a large-scale quantum computer in practice. In this work, we study the central spin decoherence problem in the $XXX$ central spin model (CSM) and focus on the quantum…

Quantum Physics · Physics 2020-11-10 Qing-Kun Wan , Hai-Long Shi , Xu Zhou , Xiao-Hui Wang , Wen-Li Yang

The loss of coherence in quantum mechanical superposition states limits the time for which quantum information remains useful. Similarly, it limits the distance over which quantum information can be transmitted, resembling Anderson…

Quantum Physics · Physics 2010-06-11 Gonzalo A. Alvarez , Dieter Suter

We study the time evolution of a single spin coupled inhomogeneously to a spin environment. Such a system is realized by a single electron spin bound in a semiconductor nanostructure and interacting with surrounding nuclear spins. We find…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 John Schliemann , Alexander V. Khaetskii , Daniel Loss

This study concerns with the dynamics of a quantum neural network unit in order to examine the suitability of simple neural computing tasks. More specifically, we examine the dynamics of an interacting spin model chosen as a candidate of a…

Quantum Physics · Physics 2017-11-23 Deniz Türkpençe , Tahir Çetin Akıncı , Serhat Şeker

Quantum networks are an integral component in performing efficient computation and communication tasks that are not accessible using classical systems. A key aspect in designing an effective and scalable quantum network is generating…

Quantum Physics · Physics 2018-07-10 Sudipto Singha Roy , Himadri Shekhar Dhar , Debraj Rakshit , Aditi Sen De , Ujjwal Sen

In this review, we discuss the decoherence and thermalization of a quantum spin system interacting with a spin bath environment, by numerically solving the time-dependent Schr\"{o}dinger equation of the whole system. The effects of the…

Quantum Physics · Physics 2010-05-27 Shengjun Yuan

Computer simulations of decoherence in quantum spin systems require the solution of the time-dependent Schrodinger equation for interacting quantum spin systems over extended periods of time. We use exact diagonalization, Chebyshev…

Quantum Physics · Physics 2007-05-23 H. De Raedt , V. V. Dobrovitski

We consider experimentally feasible chains of trapped ions with pseudo-spin 1/2, and find models that can potentially be used to implement error-resistant quantum computation. Similar in spirit to classical neural networks, the…

Quantum Physics · Physics 2009-10-20 Sibylle Braungardt , Aditi Sen De , Ujjwal Sen , Maciej Lewenstein

It has become common practice to model large spin ensembles as an effective pseudospin with total angular momentum J = N x j, where j is the spin per particle. Such approaches (at least implicitly) restrict the quantum state of the ensemble…

Quantum Physics · Physics 2012-01-24 Ben Q. Baragiola , Bradley A. Chase , JM Geremia

Quantum states are described by wave functions whose phases cannot be directly measured, but which play a vital role in quantum effects such as interference and entanglement. The loss of the relative phase information, termed decoherence,…

Chemical Physics · Physics 2019-12-20 Jia Chen , Cong Hu , John F. Stanton , Stephen Hill , Hai-Ping Cheng , Xiao-Guang Zhang

With the overwhelming success in the field of quantum information in the last decades, the "quest" for a Quantum Neural Network (QNN) model began in order to combine quantum computing with the striking properties of neural computing. This…

Quantum Physics · Physics 2014-09-01 M. Schuld , I. Sinayskiy , F. Petruccione

We investigate the decoherence of a spin 1/2 subsystem weakly coupled to an environment of many spins 1/2 with and without mutual coupling. The total system is closed, its state is pure and evolves under Schroedinger dynamics. Nevertheless,…

Quantum Physics · Physics 2009-11-11 Harry Schmidt , Guenter Mahler