Magnetoresistivity of pseudocubic manganites in the AFM phase
Abstract
Depending on carriers' concentration, the pseudocubic manganites A_1-xB_xMnO3 reveal a rich variety of magnetic and conducting properties. Among interesting findings, there was the observation of the layered AFM phase (so-called A-phase) for the (La,Sr) system in the range 0.45< x <0.8. This phase is of potential practical interest, as it shows the spin-valve effect. More recently the GMR-type of heterostructures of alternating FM- and A-phases has been prepared and studied [2]. The results showed a pronounced magnetoresistance behavior. According to [1] in such systems with the local tolerance factor close to one, thermal and kinetic properties may be interpreted in terms of the tight-binding two-band model. We have found an electronic spectrum for both FM- and A-phase in the two-band model. Based on it, conductivity and magnetoresistance effects due to scattering on defects have been described. Our approach can be also applied to discuss transport properties in manganite heterostructures. In addition, we consider the possible use of A-phase as a weak link in the Josephson contacts. M. D. and L. G. were supported by DARPA through the Naval Research Laboratory Grant No. N00173-00-1-6005 and by the NHMFL through the NSF cooperative agreement No. DMR-9521035 and the State of Florida. V.Z. was supported by DARPA under Contract No. 01J543. [1] M. Izumi et. al., Phys. Rev. B 61, 12187 (2000). [2] M. Dzero, L. P. Gor'kov and V. Z. Kresin, Eur. Phys. J. B 14, 459 (2000).
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2002
- Bibcode:
- 2002APS..MARJ16002D