skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effect of phase separation induced supercooling on magnetotransport properties of epitaxial La{sub 5/8−y}Pr{sub y}Ca{sub 3/8}MnO{sub 3} (y≈0.4) thin film

Journal Article · · AIP Advances
DOI:https://doi.org/10.1063/1.4913508· OSTI ID:22454459
 [1]; ; ; ; ;  [2]
  1. National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K. S. Krishnan Marg, New Delhi-110012 (India)
  2. Department of Applied Physics, Delhi Technological University, Delhi-110042 (India)

Thin films of La{sub 5/8−y}Pr{sub y}Ca{sub 3/8}MnO{sub 3} (y≈0.4) have been grown on single crystal SrTiO{sub 3} (001) by RF sputtering. The structural and surface characterizations confirm the epitaxial nature of these film. However, the difference between the ω-scan of the (002) and (110) peaks and the presence of pits/holes in the step-terrace type surface morphology suggests high density of defect in these films. Pronounced hysteresis between the field cooled cooling (FCC) and field cooled warming (FCW) magnetization measurements suggest towards the non-ergodic magnetic state. The origin of this nonergodicity could be traced to the magnetic liquid like state arising from the delicacy of the coexisting magnetic phases, viz., ferromagnetic and antiferromagnetic-charge ordered (FM/AFM-CO). The large difference between the insulator metal transitions during cooling and warming cycles (T{sub IM}{sup C} ∼ 64 K and T{sub IM}{sup W} ∼ 123 K) could be regarded as a manifestation of the nonergodicity leading to supercooling of the magnetic liquid while cooling. The nonergodicity and supercooling are weakened by the AFM-FM phase transition induced by an external magnetic field. T{sub IM} and small polaron activation energy corresponding the magnetic liquid state (cooling cycle) vary nonlinearly with the applied magnetic field but become linear in the crystalline solid state (warming cycle). The analysis of the low temperature resistivity data shows that electron-phonon interaction is drastically reduced by the applied magnetic field. The resistivity minimum in the lower temperature region of the self-field warming curve has been explained in terms of the Kondo like scattering in the magnetically inhomogeneous regime.

OSTI ID:
22454459
Journal Information:
AIP Advances, Vol. 5, Issue 2; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
Country of Publication:
United States
Language:
English