Spin-glass dynamics in the presence of a magnetic field: exploration of microscopic properties

Citation
Abstract
The synergy between experiment, theory, and simulations enables a microscopic analysis of spin-glass dynamics in a magnetic field in the vicinity of and below the spin-glass transition temperature T-g. The spin-glass correlation length, xi(t, t(w); T), is analysed both in experiments and in simulations in terms of the waiting time t(w) after the spin glass has been cooled down to a stabilised measuring temperature T < T-g and of the time t after the magnetic field is changed. This correlation length is extracted experimentally for a CuMn 6 at. % single crystal, as well as for simulations on the Janus II special-purpose supercomputer, the latter with time and length scales comparable to experiment. The non-linear magnetic susceptibility is reported from experiment and simulations, using xi(t, t(w); T) as the scaling variable. Previous experiments are reanalysed, and disagreements about the nature of the Zeeman energy are resolved. The growth of the spin-glass magnetisation in zero-field magnetisation experiments, M-ZFC(t, t(w); T), is measured from simulations, verifying the scaling relationships in the dynamical or non-equilibrium regime. Our preliminary search for the de Almeida-Thouless line in D = 3 is discussed.
Research Projects
Organizational Units
Journal Issue
Description
© 2021 IOP Publishing Ltd We are grateful for helpful discussions with S Swinnea about sample characterisation. This work was partially supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Materials Science and Engineering, under Award No. DE-SC0013599, and Contract No. DE-AC02-07CH11358. We were partly funded as well by Ministerio de Economia, Industria y Competitividad (MINECO, Spain), Agencia Estatal de Investigacion (AEI, Spain), and Fondo Europeo de Desarrollo Regional (FEDER, EU) through Grants No. FIS2016-76359-P, No. PID2019-103939RB-I00, No. PGC2018-094684-B-C21 and PGC2018-094684-B-C22, by the Junta de Extremadura (Spain) and Fondo Europeo de Desarrollo Regional (FEDER, EU) through Grant Nos. GRU18079 and IB15013 and by the DGA-FSE (Diputaci ' on General de Aragon-Fondo Social Europeo). This project has also received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant No. 694925 LotGlasSy). D Y was supported by the Chan Zuckerberg Biohub and IGAP was supported by the Ministerio de Ciencia, Innovacion y Universidades (MCIU, Spain) through FPU Grant No. FPU18/02665. B S was supported by the Comunidad de Madrid and the Complutense University of Madrid (Spain) through the Atraccion de Talento programme (reference 2019-T1/TIC-12776). The simulations of section 5.6.2 were carried out at the ICCAEx supercomputer centre in Badajoz. We thank the staff at ICCAEx for their assistance.
Unesco subjects
Keywords
Collections