Eur. Phys. J. B (2015) 88: 127
https://doi.org/10.1140/epjb/e2015-60197-y

Regular Article

Anomalous response in the vicinity of spontaneous symmetry breaking

¹ Department of PhysicsPukyong National University, 608-737 Busan, Korea
² Department of Physics, Sungkyunkwan University, 440-746 Suwon, Korea

^a e-mail: seungki@pknu.ac.kr
^b e-mail: beomjun@skku.edu

Received: 11 March 2015
Received in final form: 12 April 2015
Published online: 18 May 2015

Abstract

We propose a mechanism to induce negative AC permittivity in the vicinity of a ferroelectric phase transition involved with spontaneous symmetry breaking. This mechanism makes use of responses at low frequency, yielding a high gain and a large phase delay, when the system jumps over the free-energy barrier with the aid of external fields. We illustrate the mechanism by analytically studying spin models with the Glauber-typed dynamics under periodic perturbations. Then, we show that the scenario is supported by numerical simulations of mean-field as well as two-dimensional spin systems.