Volume 79, Number 1, July 2007
Article Number 17005
Number of page(s) 5
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 15 June 2007
EPL, 79 (2007) 17005
DOI: 10.1209/0295-5075/79/17005

Enhancement of electronic transport and magnetoresistance of $\chem{Al_{2}O_{3}}$-impregnated $\chem{(La_{0.5}Pr_{0.2}) Sr_{0.3}MnO_{3}}$ thin films

J. H. Markna1, P. S. Vachhani1, R. N. Parmar1, D. G. Kuberkar1, P. Misra2, B. N. Singh2, L. M. Kukreja2, D. S. Rana3 and S. K. Malik4

1  Department of Physics, Saurashtra University - Rajkot 360005, India
2  Thin Film Laboratory, Raja Ramanna Center for Advance Technology - Indore 452 013, India
3  Institute of Laser Engineering, Osaka University - Osaka 565 0871, Japan
4  International Center for Condensed Matter Physics (ICCMP) University of Brasilia - Brasilia, Brazil

received 11 April 2007; accepted in final form 22 May 2007; published July 2007
published online 15 June 2007

We have used a non-magnetic ${\rm Al}_{2}{\rm O}_{3}$ barrier, impregnated in $({\rm La}_{0.5}{\rm Pr}_{0.2}){\rm Sr}_{0.3}{\rm MnO}_{3}$ (LPSMO) thin film layers, to obtain large magnetoresistance (MR) in the vicinity of room temperature. In the magnetic field of 1T, the LPSMO/ ${\rm Al}_{2}{\rm O}_{3}$/LPSMO heterostructure exhibits an MR of $\sim 35{\%}$ at its insulator-to-metal transition temperature ( $T_{{\rm IM}}$) of $\sim 220\,{\rm K}$ vis-à-vis an MR of $\sim 8{\%}$ in the pristine LPSMO film at its $T_{{\rm IM}}$ of 298 K. This enhanced MR, coupled with a 2- to 3-fold increase in the temperature coefficient of resistance and the field coefficient of resistance in the heterostructure compared to that in the LPSMO films, demonstrates the efficiency of this technique in engineering those physical properties of manganites which have potential bearing on the realization of their technological applications.

72.25.Mk - Spin transport through interfaces .

© Europhysics Letters Association 2007