UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Microscopic aspects of magnetic lattice demagnetizing factors

Twengström, M; Bovo, L; Gingras, MJP; Bramwell, ST; Henelius, P; (2017) Microscopic aspects of magnetic lattice demagnetizing factors. Physical Review Materials , 1 , Article 044406. 10.1103/PhysRevMaterials.1.044406. Green open access

[img]
Preview
Text
Bramwell_Microscopic Aspects of Magnetic Lattice Demagnetizing Factors.pdf - Published version

Download (534kB) | Preview

Abstract

The demagnetizing factor N is of both conceptual interest and practical importance. Considering localized magnetic moments on a lattice, we show that for nonellipsoidal samples, N depends on the spin dimensionality (Ising, XY, or Heisenberg) and orientation, as well as the sample shape and susceptibility. The generality of this result is demonstrated by means of a recursive analytic calculation as well as detailed Monte Carlo simulations of realistic model spin Hamiltonians. As an important check and application, we also make an accurate experimental determination of N for a representative collective paramagnet (i.e., the Dy_2Ti_2O_7 spin ice compound) and show that the temperature dependence of the experimentally determined N agrees closely with our theoretical calculations. Our conclusion is that the well-established practice of approximating the true sample shape with “corresponding ellipsoids” for systems with long-range interactions will in many cases overlook important effects stemming from the microscopic aspects of the system under consideration.

Type: Article
Title: Microscopic aspects of magnetic lattice demagnetizing factors
Open access status: An open access version is available from UCL Discovery
DOI: 10.1103/PhysRevMaterials.1.044406
Publisher version: https://doi.org/10.1103/PhysRevMaterials.1.044406
Language: English
Additional information: This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: Condensed matter & Material physics, Statistical physics, Dipolar interaction, Magnetic susceptibility, Magnetism, Magnetic insulators, Finite-size scaling, Ising model, Mean field theory, Monte Carlo methods, Spin lattice models, Susceptibility measurements
UCL classification: UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy
UCL > Provost and Vice Provost Offices > VP Innovation and Enterprise
UCL > Provost and Vice Provost Offices > VP Innovation and Enterprise > Business and Innovation Partnerships
URI: https://discovery.ucl.ac.uk/id/eprint/1539808
Downloads since deposit
71Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item