Domain dynamics in the multiferroic phase of MnWO4

Article

关键词: E HYSTERESIS LOOP;    AVRAMI MODEL;    POLARIZATION;   

DOI  :  10.1103/PhysRevB.89.134412

来源: SCIE

【 摘 要 】

By using broadband linear and nonlinear dielectric spectroscopy we studied the magnetoelectric dynamics in the chiral antiferromagnet MnWO4. In the multiferroic phase the dielectric response is dominated by the dynamics of domains and domain walls which is strongly dependent on the stimulating electric field. The mean switching time reaches values in the minute range in the middle of the multiferroic temperature regime at T approximate to 10 K but unexpectedly decays again on approaching the lower, first-order phase boundary at T-N1 approximate to 7.6 K. The switchability of the ferroelectric domains denotes a pinning-induced threshold and can be described considering a growth-limited scenario with an effective growth dimension of d approximate to 1.8. The rise of the effective dynamical coercive field on cooling below the T-N2 is much stronger compared to the usual ferroelectrics and can be described by a power law E-c proportional to nu(1/2). The latter questions the feasibility of fast-switching devices based on this type of material.

【 授权许可】

Free