Memory Effect in Thin Thermocycling-modified La0.67Ca0.33MnO3 Films

  • Fiodoras ANISIMOVAS Center for Physical Sciences and Technology
  • Steponas AŠMONTAS Center for Physical Sciences and Technology
  • Jonas GRADAUSKAS Center for Physical Sciences and Technology
  • Oleg KIPRIJANOVIČ Center for Physical Sciences and Technology
  • Bonifacas VENGALIS Center for Physical Sciences and Technology
Keywords: manganite thin films, thermocycling, highly resistive states, martensitic-type transformations, memory effect

Abstract

Nonhomogeneous thin La0.67Ca0.33MnO3 films, having Tm in 180 K200 K temperature range, were thermocycled between 80 K and 210 K using liquid nitrogen. After the thermocycling it was confirmed formation of highly resistive state with additional low temperature peak of resistance with maximum at 115 K when measuring R-T plots. Measurements of electroresistive effect in this state using low dc of different values and performed in cooling run reveal discontinuities of R-T plots. It is proposed formation of two different high resistive states: at low temperatures and at vicinity of  Tm. The discontinuities disclose switching between these two states initiated by substrate-induced long-range strain and by manifestation of memory effect. This interpretation of experimental results explains appearing of low temperature peak based on influence of the long-range strains on formation of high resistive interlayers in the film during the thermocycling. We argue that the interlayers acquire memory properties after being modified by martensitic-type transformations.

DOI: http://dx.doi.org/10.5755/j01.ms.18.1.1333

Published
2012-03-15
Section
ELECTRONIC AND OPTICAL MATERIALS