Webbläsaren som du använder stöds inte av denna webbplats. Alla versioner av Internet Explorer stöds inte längre, av oss eller Microsoft (läs mer här: * https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Var god och använd en modern webbläsare för att ta del av denna webbplats, som t.ex. nyaste versioner av Edge, Chrome, Firefox eller Safari osv.

Metamagnetism and soliton excitations in the modulated ferromagnetic Ising chain CoV2O6

Författare

  • Simon A. J. Kimber
  • Hannu Mutka
  • Tapan Chatterji
  • Tommy Hofmann
  • Paul Henry
  • Heloisa Bordallo
  • Dimitri Argyriou
  • J. Paul Attfield

Summary, in English

We report a combination of physical property and neutron scattering measurements for polycrystalline samples of the one-dimensional spin-chain compound CoV2O6. Heat capacity measurements show that an effective S = 1/2 state is found at low temperatures and that magnetic fluctuations persist up to similar to 6T(N). Above T-N = 6.3 K, measurements of the magnetic susceptibility as a function of T and H show that the nearest-neighbor exchange is ferromagnetic. In the ordered state, we have discovered a crossover from a metamagnet with strong fluctuations between 5 K and T-N to a state with a 1/3 magnetization plateau at 2 < T < 5 K. We use neutron powder diffraction measurements to show that the antiferromagnetic state has incommensurate long-range order and inelastic time-of-flight neutron scattering to examine the magnetic fluctuations as a function of temperature. Above T-N, we find two broad bands between 3.5 and 5 meV and thermally activated low-energy features which correspond to transitions within these bands. These features show that the excitations are deconfined solitons rather than the static spin reversals predicted for a uniform ferromagnetic Ising spin chain. Below T-N, we find a ladder of states due to the confining effect of the internal field. A region of weak confinement below T-N, but above 5 K, is identified which may correspond to a crossover between two- and three-dimensional magnetic ordering.

Publiceringsår

2011

Språk

Engelska

Publikation/Tidskrift/Serie

Physical Review B (Condensed Matter and Materials Physics)

Volym

84

Issue

10

Dokumenttyp

Artikel i tidskrift

Förlag

American Physical Society

Ämne

  • Physical Sciences
  • Natural Sciences

Status

Published

ISBN/ISSN/Övrigt

  • ISSN: 1098-0121