Electrical transport and magnetoresistance properties of La(0.67)Ca(0.33)Mno(3) film coated on pyrex glass substrate


GENÇER H., Goktas A., Gunes M., Mutlu H. I., ATALAY S.

INTERNATIONAL JOURNAL OF MODERN PHYSICS B, vol.22, no.5, pp.497-506, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 22 Issue: 5
  • Publication Date: 2008
  • Doi Number: 10.1142/s0217979208038776
  • Journal Name: INTERNATIONAL JOURNAL OF MODERN PHYSICS B
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.497-506
  • Keywords: manganite films, colossal magnetoresistance, strain effect, Coulomb blockade, upturn of the resistance, MAGNETIC ENTROPY-CHANGE, COLOSSAL MAGNETORESISTANCE, THIN-FILMS, GIANT MAGNETORESISTANCE, THICKNESS DEPENDENCE, PHASE-DIAGRAM, STRAIN, TEMPERATURE, RESISTIVITY, EXCHANGE
  • Akdeniz University Affiliated: No

Abstract

The electrical transport and magnetoresistance properties of the polycrystalline La0.67Ca0.33MnO3 film produced on a Pyrex substrate were investigated for the first time. X-ray powder diffraction indicated that the film sample has a perovskite structure. Scanning electron microscope indicated that La0.67Ca0.33MnO3 film thickness is approximately 500 nm, and the average grain size of this sample varies between 40 and 50 nm. La0.67Ca0.33MnO3 film showed a phase transition from paramagnetic to ferromagnetic at (T-C) 80 K and a metal insulator transition at (T-MI) 77.5 K and at 2 mT magnetic field. The upturn of the resistance observed at low temperatures (<36 K) was attributed to the Coulomb blockade, and the strong structural disorder is due to the large lattice mismatch and strain relaxation. A large magnetoresistance ratio [MR %] of 780% was observed at 100 K and 6 T magnetic field.