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相关论文: Pseudorandom Selective Excitation in NMR

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The reversal of the time evolution of the local polarization in an interacting spin system involves a sign change of the effective dipolar Hamiltonian which refocuses the 'spin diffusion' process generating a polarization echo. Here, the…

凝聚态物理 · 物理学 2009-10-30 Patricia R. Levstein , Gonzalo Usaj , Horacio M. Pastawski

Discrete event systems are present both in observations of nature, socio economical sciences, and industrial systems. Standard analysis approaches do not usually exploit their dual event / state nature: signals are either modeled as…

人工智能 · 计算机科学 2025-12-02 Sylvain Marié , Pablo Knecht

Driven many-body quantum systems where some parameter in the Hamiltonian is varied quasiperiodically in time may exhibit nonequilibrium steady states that are qualitatively different from their periodically driven counterparts. Here we…

强关联电子 · 物理学 2018-12-27 Sourav Nandy , Arnab Sen , Diptiman Sen

We consider the effect of disorder on the tight-binding Hamiltonians with a flat band and derive a common mathematical formulation of the average density of states and inverse participation ratio applicable for a wide range of them. The…

无序系统与神经网络 · 物理学 2018-09-12 Pragya Shukla

Using the intertwining relation we construct a pseudosuperpartner for a (non-Hermitian) Dirac-like Hamiltonian describing a two-level system interacting in the rotating wave approximation with the electric component of an electromagnetic…

量子物理 · 物理学 2009-11-11 Boris F Samsonov , V V Shamshutdinova

The resonant activation phenomenon (RAP) in a discrete system is studied using the master equation formalism. We show that the RAP corresponds to a non-monotonic behavior of the frequency dependent first passage time probability density…

其他凝聚态物理 · 物理学 2007-05-23 O. Flomenbom , J. Klafter

In pulsed dynamic nuclear polarization (DNP), enhancement of the polarization of bulk nuclei requires the repeated application of a microwave pulse sequence. So far, analysis of a one-time transfer of electron spin polarization to a…

Hybrid machine learning based on Hamiltonian formulations has recently been successfully demonstrated for simple mechanical systems, both energy conserving and not energy conserving. We introduce a pseudo-Hamiltonian formulation that is a…

机器学习 · 计算机科学 2023-02-15 Sølve Eidnes , Alexander J. Stasik , Camilla Sterud , Eivind Bøhn , Signe Riemer-Sørensen

We study the effect of quantum fluctuations on the half-polarized magnetization plateau of a pyrochlore antiferromagnet. We argue that an expansion around the easy axis limit is appropriate for discussing the ground state selection amongst…

强关联电子 · 物理学 2007-05-23 Doron L. Bergman , Ryuichi Shindou , Gregory A. Fiete , Leon Balents

We analyse the stochastic properties of the 49 pulsars that comprise the first International Pulsar Timing Array (IPTA) data release. We use Bayesian methodology, performing model selection to determine the optimal description of the…

Sustained rhythmic oscillations, pulsing dynamics, emerge spontaneously when the local connection scheme is randomised in 3-value cellular automata that feature"glider" dynamics. Time-plots of pulsing measures maintain a distinct waveform…

元胞自动机与格子气 · 物理学 2021-03-02 Andrew Wuensche , Edward Coxon

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…

量子物理 · 物理学 2007-05-23 K. Khodjasteh , D. A. Lidar

For resonant slow extraction of accelerated particle beams from synchrotrons, a 3rd order resonance driven by sextupole magnets is commonly used. This note reviews the non-linear particle dynamics under these conditions as described by the…

加速器物理 · 物理学 2024-03-27 Philipp Niedermayer

We demonstrate selective excitation of a spin wave mode in a ferromagnetic (Ga,Mn)As film by picosecond strain pulses. For a certain range of magnetic fields applied in the layer plane only a single frequency is detected for the…

We analytically investigate the one-excitation spin dynamics in a homogeneous closed spin-1/2 chain via diagonalization of the one-excitation block of the XX-Hamiltonian, which allows to derive the analytical expressions for probability…

量子物理 · 物理学 2024-02-01 E. B. Fel'dman , E. I. Kuznetsova , A. I. Zenchuk

We extend profile domain pulsar timing to incorporate wide-band effects such as frequency-dependent profile evolution and broadband shape variation in the pulse profile. We also incorporate models for temporal variations in both pulse width…

We study the behaviour of discrete dynamical systems generated by a continuous map $f$ of a compact real interval into itself where at randomly chosen times a function different from $f$ - so called impulse function is applied. We show that…

动力系统 · 数学 2024-10-25 J. Kováč , J. Veselý , K. Janková

We study the long-term average evolution of the random ensemble along integrable Hamiltonian systems with time $T$-periodic transitions. More precisely, for any observable $G$, it is demonstrated that the ensemble under $G$ in long time…

动力系统 · 数学 2023-11-27 Xinyu Liu , Yong Li

We study the dynamics of excitable integrate-and-fire neurons in a small-world network. At low densities $p$ of directed random connections, a localized transient stimulus results in either self-sustained persistent activity or in a brief…

斑图形成与孤子 · 物理学 2009-11-10 Alex Roxin , Hermann Riecke , Sara A. Solla

Quantum-disordered models provide a versatile platform to explore the emergence of quantum excitations in many-body systems. The engineering of spin models at the atomic scale with scanning tunneling microscopy and the local imaging of…

介观与纳米尺度物理 · 物理学 2023-08-23 Netta Karjalainen , Zina Lippo , Guangze Chen , Rouven Koch , Adolfo O. Fumega , Jose L. Lado