Title :
Large magnetoresistance in La-Ca-Mn-O films
Author :
Chen, L.H. ; Jin, S. ; Tiefel, T.H. ; Ramesh, R. ; Schurig, D.
Author_Institution :
Kaohsiung Polytech. Inst., Ta-Hsu Hsiang, Taiwan
fDate :
11/1/1995 12:00:00 AM
Abstract :
A very large magnetoresistance value in excess of 106% has been obtained at 110 K, H=6T in La-Ca-Mn-O thin films epitaxially grown on LaAlO3 substrates by pulsed laser deposition. The as-deposited film exhibits a substantial magnetoresistance value of 39,000%, which is further improved by heat treatment. A strong dependence of the magnetoresistance on film thickness was observed, with the value reduced by orders of magnitude when the film is made thicker than ~2000 Å. This behavior is interpreted in terms of lattice strain in the La-Ca-Mn-O films
Keywords :
calcium compounds; ferromagnetic materials; giant magnetoresistance; heat treatment; internal stresses; lanthanum compounds; magnetic epitaxial layers; magnetoresistance; pulsed laser deposition; vapour phase epitaxial growth; 110 K; 2000 A; 6 T; La-Ca-Mn-O; La-Ca-Mn-O films; LaAlO3; LaAlO3 substrates; as-deposited film; epitaxial film; ferromagnetic film; film thickness dependence; heat treatment; large magnetoresistance; lattice strain; pulsed laser deposition; thin films; Atmosphere; Conductivity; Electric resistance; Heat treatment; Magnetic materials; Magnetoresistance; Optical pulses; Pulsed laser deposition; Sputtering; Substrates;
Journal_Title :
Magnetics, IEEE Transactions on
