The coupling between localized spins and phonons can lead to shifts in the dielectric constant of insulating materials at magnetic ordering transitions. Studies on isostructural SeCuO3 (ferromagnetic) and TeCuO3 (antiferromagnetic) illustrate how the q-dependent spin-spin correlation function couples to phonon frequencies leading to a shift in the dielectric constant. A model is discussed for this spin-phonon coupling. The magnetodielectric coupling in multiferroic materials can be very large at a ferroelectric transition temperature. This coupling is investigated in the recently identified multiferroic Ni3V2O8.
@article{arxiv.0904.1974,
title = {Magnetically tunable dielectric materials},
author = {G. Lawes and T. Kimura and C. M. Varma and M. A. Subramanian and R. J. Cava and A. P. Ramirez},
journal= {arXiv preprint arXiv:0904.1974},
year = {2009}
}
Comments
4 pages, 3 figures. Originally appeared in: The Twelfth US-Japan Seminar on Dielectric and Piezoelectric Ceramics, p. 215 (2005) (unpublished conference proceedings). The manuscript has not been modified or updated in any way from this version