English
Related papers

Related papers: Decoherence in a quantum neural network

200 papers

Previously a new scheme of quantum information processing based on spin coherent states of two component Bose-Einstein condensates was proposed (Byrnes {\it et al.} Phys. Rev. A 85, 40306(R)). In this paper we give a more detailed…

We investigate the time evolution of entanglement under various models of decoherence: A general heuristic model based on local relaxation and dephasing times, and two microscopic models describing decoherence of electron spin qubits in…

Mesoscale and Nanoscale Physics · Physics 2009-09-02 F. Bodoky , O. Gühne , M. Blaauboer

Quantum coherence is an essential resource to gain advantage over classical physics and technology. Recently, it has been proposed that a low-temperature environment can induce quantum coherence of a spin without an external coherent pump.…

Quantum Physics · Physics 2022-04-20 Artur Slobodeniuk , Tomáš Novotný , Radim Filip

We theoretically study the interaction of a heavy hole with nuclear spins in a quasi-two-dimensional III-V semiconductor quantum dot and the resulting dephasing of heavy-hole spin states. It has frequently been stated in the literature that…

Mesoscale and Nanoscale Physics · Physics 2008-11-03 Jan Fischer , W. A. Coish , D. V. Bulaev , Daniel Loss

A new paradigm of quantum computing, namely, soft quantum computing, is proposed for nonclassical computation using real world quantum systems with naturally occurring environment-induced decoherence and dissipation. As a specific example…

Quantum Physics · Physics 2018-10-12 Zeng-Bing Chen

We consider a linear quench from the paramagnetic to ferromagnetic phase in the quantum Ising chain interacting with a static spin environment. Both decoherence from the environment and non-adiabaticity of the evolution near a critical…

Quantum Physics · Physics 2016-09-08 Lukasz Cincio , Jacek Dziarmaga , Jakub Meisner , Marek M. Rams

The difference in the properties of the spin correlation tensor for factorizable and nonfactorizable two-particle states is analyzed. The inequalities for linear combinations of the components of this tensor are obtained for the case of…

High Energy Physics - Phenomenology · Physics 2009-11-07 R. Lednicky , V. Lyuboshitz

Nonequilibrium phases of quantum matter featuring time crystalline eigenstate order have been realized recently on noisy intermediate-scale quantum (NISQ) devices. While ideal quantum time crystals exhibit collective subharmonic…

Strongly Correlated Electrons · Physics 2024-07-26 Gonzalo Camacho , Benedikt Fauseweh

The growth in the demand for precisely crafted many-body systems of spin-$1/2$ particles/qubits is due to their top-notch versatility in application-oriented quantum-enhanced protocols and the fundamental tests of quantum theory. Here we…

Quantum Physics · Physics 2020-10-14 Artur Niezgoda , Miłosz Panfil , Jan Chwedeńczuk

We propose and analyze an efficient high-dimensional quantum state transfer protocol in an XX coupling spin network with a hypercube structure or chain structure. Under free spin wave approximation, unitary evolution results in a perfect…

Quantum Physics · Physics 2015-03-18 Wei Qin , Jun-Lin Li , Gui-Lu Long

We revisit the concepts of spin relaxation and spin decoherence of two level (spin-1/2) systems. From two toy-models, we clarify two issues related to the spin relaxation and decoherence: 1) For an ensemble of two-level particles each…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 X. R. Wang , Y. S. Zheng , Sun Yin

We demonstrate the extension of coherence between all four two-electron spin ground states of an InAs quantum dot molecule (QDM) via non-local suppression of nuclear spin fluctuations in both constituent quantum dots (QDs), while optically…

Mesoscale and Nanoscale Physics · Physics 2016-08-17 Colin M. Chow , Aaron M. Ross , Danny Kim , Daniel Gammon , Allan S. Bracker , L. J. Sham , Duncan G. Steel

Stroboscopic spin flips have already been shown to prolong the coherence times of quantum systems under noisy environments. Uhrig's dynamical decoupling scheme provides an optimal sequence for a quantum system interacting with a dephasing…

Quantum Physics · Physics 2011-10-10 Soumya Singha Roy , T. S. Mahesh , G. S. Agarwal

The realisation of quantum computers based on molecular electronic spins requires the design of qubits with very long coherence times, T2. Dephasing can proceed over several different microscopic pathways, active at the same time and in…

Materials Science · Physics 2020-01-08 Alessandro Lunghi , Stefano Sanvito

Quantum coherence conservation is shown to be achieved by a very high rate of dissipation of an environmental system coupled with a principal system. This effect is not in the list of previously-known strategies of noise suppression, such…

Quantum Physics · Physics 2007-10-24 Akira SaiToh , Robabeh Rahimi , Mikio Nakahara

We study the behavior of a quantum gyroscope, that is, a quantum system which singles out a direction in space in order to measure certain properties of incoming particles such as the orientation of their spins. We show that repeated…

Quantum Physics · Physics 2013-02-07 Olivier Landon-Cardinal , Richard MacKenzie

Quantum computing is expected to provide new promising approaches for solving the most challenging problems in material science, communication, search, machine learning and other domains. However, due to the decoherence and gate…

Quantum Physics · Physics 2020-04-22 Oleg M. Sotnikov , Vladimir V. Mazurenko

In semiconductors, the T2* coherence time of a single confined spin is limited either by the fluctuating magnetic environment (via the hyperfine interaction), or by charge fluctuations (via the spin-orbit interaction). We demonstrate that…

Mesoscale and Nanoscale Physics · Physics 2012-04-13 K. M. Weiss , J. M. Elzerman , Y. L. Delley , J. Miguel-Sanchez , A. Imamoglu

We study quantum coherence in a spin chain with both symmetric exchange and antisymmetric Dzyaloshinsky-Moriya couplings. Quantum coherence is quantified using the recently introduced quantum Jensen-Shannon divergence, which has the…

The works on decoherence due to spin baths usually agree in studying a one-spin system in interaction with a large spin bath. In this paper we generalize those models by analyzing a many-spin system and by studying decoherence or its…

Quantum Physics · Physics 2010-01-21 Mario Castagnino , Sebastian Fortin , Olimpia Lombardi