Skip to Main content Skip to Navigation
Journal articles

Magnetodielectric coupling and multi-blocking effect in the Ising-chain magnet Sr 2 Ca 2 CoMn 2 O 9

Abstract : We have demonstrated magnetodielectric (MD) coupling in an Ising-chain magnet Sr 2 Ca 2 CoMn 2 O 9 via detailed investigation of ac susceptibility and dielectric constant as a function of temperature, magnetic field, and frequency. Sr 2 Ca 2 CoMn 2 O 9 consists of spin-chains made of the regular stacking of one CoO 6 trigonal prism with two MnO 6 octahedra. The (Co 2+-Mn 4+-Mn 4+) unit stabilizes a (↑↓↑) spin-state along the chains that are distributed on a triangular lattice. This compound undergoes a partially disordered antiferromagnetic transition at T N ∼ 28 K. The dielectric constant exhibits a clear peak at T N only in the presence of an external magnetic field (H ≥ 5 kOe), evidencing the presence of MD coupling, which is further confirmed by field-dependent dielectric measurements. We argue that spatial inversion symmetry can be broken as a result of exchange-striction along each spin chain, inducing uncompensated local dipoles. At low temperatures, a dipolar relaxation phenomenon is observed, bearing strong similarities to the blocking effect typical of spin dynamics in this compound. Such a spin-dipole relationship is referred to as a "multiblocking" effect, in relation to the concept of magnetodielectric "multiglass" previously introduced for related materials.
Complete list of metadata

https://hal-cnrs.archives-ouvertes.fr/hal-03429358
Contributor : Olivier Perez Connect in order to contact the contributor
Submitted on : Thursday, November 18, 2021 - 4:08:02 PM
Last modification on : Friday, November 19, 2021 - 3:46:11 AM

File

Magnetodielectric coupling (1)...
Files produced by the author(s)

Identifiers

Citation

T. Basu, N. Sakly, A. Pautrat, F. Veillon, O. Pérez, et al.. Magnetodielectric coupling and multi-blocking effect in the Ising-chain magnet Sr 2 Ca 2 CoMn 2 O 9. Journal of Applied Physics, American Institute of Physics, 2021, 130 (3), pp.034102. ⟨10.1063/5.0056149⟩. ⟨hal-03429358⟩

Share

Metrics

Record views

8

Files downloads

12