English
Related papers

Related papers: Pulse-noise approach for classical spin systems

200 papers

We consider pulses of finite duration for coherent control in the presence of classical noise. We derive the corrections to ideal, instantaneous pulses for the case of general decoherence (spin-spin relaxation and spin-lattice relaxation)…

Quantum Physics · Physics 2012-10-17 Christopher Stihl , Benedikt Fauseweh , Stefano Pasini , Götz S. Uhrig

An understanding of pulsar timing noise offers the potential to improve the timing precision of a large number of pulsars as well as facilitating our understanding of pulsar magnetospheres. For some sources, timing noise is attributable to…

High Energy Astrophysical Phenomena · Physics 2018-02-07 B. Shaw , B. W. Stappers , P. Weltevrede

We present a cluster expansion method for approximating quantum spin-bath dynamics in terms of a classical Gaussian stochastic process. The cluster expansion produces the two-point correlation function of the approximate classical bath,…

Mesoscale and Nanoscale Physics · Physics 2014-09-30 Wayne M. Witzel , Kevin Young , Sankar Das Sarma

We analyze the complexity of classically simulating continuous-time dynamics of locally interacting quantum spin systems with a constant rate of entanglement breaking noise. We prove that a polynomial time classical algorithm can be used to…

Quantum Physics · Physics 2022-11-11 Rahul Trivedi , J. Ignacio Cirac

Dynamical decoupling pulse sequences have been used to extend coherence times in quantum systems ever since the discovery of the spin-echo effect. Here we introduce a method of recursively concatenated dynamical decoupling pulses, designed…

Quantum Physics · Physics 2007-05-23 K. Khodjasteh , D. A. Lidar

In the framework of nuclear magnetic resonance, we consider the general problem of the coherent control of a spin coupled to a bath by means of composite or continuous pulses of duration $\tau_\mathrm{p}$. We show explicity that it is…

Quantum Physics · Physics 2010-03-16 S. Pasini , P. Karbach , C. Raas , G. S. Uhrig

We investigate the correspondence between classical noise and quantum environments. Although it has been known that the classical noise can be mapped to the quantum environments only for pure dephasing and infinite-temperature dissipation…

Quantum Physics · Physics 2024-12-31 Jiarui Zeng , Guo-Hao Xu , Weijie Huang , Yao Yao

We consider the impact of stochastic perturbations on otherwise coherent oscillations of classical pulsators. The resulting dynamics are modelled by a driven damped harmonic oscillator subject to either an external or an internal forcing…

Solar and Stellar Astrophysics · Physics 2020-01-22 P. P. Avelino , M. S. Cunha , W. J. Chaplin

We provide a polynomial-time classical algorithm for noisy quantum circuits. The algorithm computes the expectation value of any observable for any circuit, with a small average error over input states drawn from an ensemble (e.g. the…

Quantum Physics · Physics 2024-10-15 Thomas Schuster , Chao Yin , Xun Gao , Norman Y. Yao

We suggest a numerical integration procedure for solving the equations of motion of certain classical spin systems which preserves the underlying symplectic structure of the phase space. Such symplectic integrators have been successfully…

Statistical Mechanics · Physics 2007-05-23 Robin Steinigeweg , Heinz-Jürgen Schmidt

Dense spin ensembles in solids present a natural platform for studying quantum many-body dynamics. Multiple-pulse coherent control can be used to manipulate the magnetic dipolar interaction between the spins to engineer their dynamics.…

Quantum Physics · Physics 2024-12-24 Linta Joseph , Wynter Alford , Chandrasekhar Ramanathan

A new Bayesian software package for the analysis of pulsar timing data is presented in the form of TempoNest which allows for the robust determination of the non-linear pulsar timing solution simultaneously with a range of additional…

Instrumentation and Methods for Astrophysics · Physics 2013-12-04 Lindley Lentati , Paul Alexander , Michael P. Hobson , Farhan Feroz , Rutger van Haasteren , Kejia Lee , Ryan M. Shannon

We consider synchronization by noise for stochastic partial differential equations which support traveling pulse solutions, such as the FitzHugh-Nagumo equation. We show that any two pulse-like solutions which start from different positions…

Probability · Mathematics 2025-01-24 Christian Kuehn , Joris van Winden

Timing noise in pulsars is often modelled with a Fourier-basis Gaussian process that follows a power law with periodic boundary conditions on the observation time, $T_\mathrm{span}$. However the actual noise processes can extend well below…

High Energy Astrophysical Phenomena · Physics 2023-06-14 Michael J. Keith , Iuliana C. Niţu

The pulse-noise approach to systems of classical spins weakly interacting with the bath has been applied to study thermally-activated escape of magnetic nanoparticles over the uniform and nonuniform energy barriers at intermediate and low…

Statistical Mechanics · Physics 2018-10-24 D. A. Garanin

The smooth spin-down of young pulsars is perturbed by two non-deterministic phenomenon, glitches and timing noise. Although the timing noise provides insights into nuclear and plasma physics at extreme densities, it acts as a barrier to…

High Energy Astrophysical Phenomena · Physics 2019-09-25 A. Parthasarathy , R. M. Shannon , S. Johnston , L. Lentati , M. Bailes , S. Dai , M. Kerr , R. N. Manchester , S. Oslowski , C. Sobey , W. van Straten , P. Weltevrede

In this work, average Hamiltonian theory is used to study selective excitation in a spin-1/2 system evolving under a series of small flip-angle $\theta-$pulses $(\theta\ll 1)$ that are applied either periodically [which corresponds to the…

Quantum Physics · Physics 2015-05-19 Jamie D. Walls , Alexandra Coomes

Avoiding the loss of coherence of quantum mechanical states is an important prerequisite for quantum information processing. Dynamical decoupling (DD) is one of the most effective experimental methods for maintaining coherence, especially…

Quantum Physics · Physics 2010-10-08 Gonzalo A. Alvarez , Ashok Ajoy , Xinhua Peng , Dieter Suter

Precision pulsar timing is integral to the detection of the nanohertz stochastic gravitational-wave background as well as understanding the physics of neutron stars. Conventional pulsar timing often uses fixed time and frequency-averaged…

Instrumentation and Methods for Astrophysics · Physics 2023-06-14 Rowina S. Nathan , Matthew T. Miles , Gregory Ashton , Paul D. Lasky , Eric Thrane , Daniel J. Reardon , Ryan M. Shannon , Andrew D. Cameron

We introduce a new characteristics of chaoticity of classical and quantum dynamical systems by defining the notion of the dissipation time which enables us to test how the system responds to the noise and in particular to measure the speed…

Chaotic Dynamics · Physics 2007-05-23 Lech Wolowski
‹ Prev 1 2 3 10 Next ›