https://doi.org/10.1007/s100510051147
Influence of high-energy electron irradiation on the transport properties of La1-xCaxMnO3)
1
B. Verkin Institute for Low Temperature Physics & Engineering, Kharkov, 310164, Ukraine
2
Kharkov State University, Kharkov, 310077, Ukraine
3
Department of Physics, Texas A& M University, College Station, TX 77843-4242, USA
Received:
21
July
1999
Revised:
27
December
1999
Published online: 15 June 2000
The effect of crystal lattice disorder on the conductivity and colossal
magnetoresistance in LaCaxMnO3 (
) films has been
examined. The lattice defects are introduced by irradiating the film with high-energy
(
MeV) electrons with a maximal fluence of about
cm-2.
This comparatively low dose of irradiation produces rather small radiation damage in
the films. The number of displacements per atom (dpa) in the irradiated sample is
about 10-5. Nevertheless, this results in an appreciable increase in the film
resistivity. The percentage of the resistivity increase in the ferromagnetic metallic
state (below the Curie temperature Tc) was much greater than that observed in the
insulating state (above Tc). At the same time irradiation has much less effect
on Tc or on the magnitude of the colossal magnetoresistance. A possible
explanation of such behavior is proposed.
PACS: 75.30.Vn – Colossal magnetoresistance / 72.80.Ga – Transition-metal compounds / 72.60.+g – Mixed conductivity and conductivity transitions
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000