Thermal activation and ac-field-induced discontinuous domain jumps in perovskite La0.7Ca0.3MnO3

X. L. Wang, University of Wollongong
J. Horvat, University of Wollongong
H. K. Liu, University of Wollongong
S. X. Dou, University of Wollongong

Article comments

This article was originally published as: Wang, XL, Horvat, J, Liu, HK & Dou, SX, Thermal activation and ac-field-induced discontinuous domain jumps in perovskite La0.7Ca0.3MnO3, Physical Review B, 1998, 58(5), 2434-2437. Copyright 1998 American Physical Society. The original journal can be found here.

Abstract

Low-field ac susceptibility was measured on bulk La0.7Ca0.3MnO3 prepared by a partial melting technique. Discontinuous jumps with heights of (1 – 2)105 emu at temperature intervals of 3–5 K were observed in the ac susceptibility. 28 jumps were observed in the temperature range between 4.2 K and the Curie temperature of 250 K, with an ac field amplitude of 1 Oe, a frequency of 117 Hz, and a dc bias field of 5 and 20 Oe. Upon increasing the frequency up to 5000 Hz, the jumps shifted to lower temperature. For a dc bias field of 50 Oe and an ac field with an amplitude of 0.1 Oe and a frequency between 117 and 5000 Hz, only three jumps with heights of about 3105 emu at large temperature intervals of about 60 K were observed for TTc . With increasing frequencies, the three jumps shifted to lower temperatures without changing jump height. The discontinuous jumps in La0.7Ca0.3MnO3 were interpreted in terms of thermally and ac-field-activated domainwall jumps.