Open AccessPeculiar transport properties and CMR effect of La0.67Sr0.08Na0.25MnO3
Author(s) -
Peng Zhen-sheng,
Yu Tang,
Guoqing Yan,
Guo Huan-yin,
Qiang Mao
Publication year - 2007
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.56.1707
Subject(s) - polaron , condensed matter physics , scattering , atmospheric temperature range , materials science , electron , physics , thermodynamics , quantum mechanics
The La0.67Sr0.08Na0.25MnO3 sample was prepared by solid-state reaction. The transport properties and CMR effect of the sample were studied through M-T curves, ρ-T curves and ρ-T fitted curves. The results show that: Both the ρ-T curves and the MR-T curve exhibit the double-peak phenomenon; the high-temperature peak corresponds to the I-M transition accompanied by the PM-FM transition, and the low-temperature peak is attributed to grain boundary effect. The two insulator phases have different transport mechanisms: in the low temperature range(248 KTρ(T) accords with variable-range-hopping model of polaron, while in the high temperature range(330 KTρ(T) accords with near- neighbor- hopping model of polaron; and the two metal-like phases also have different transport mechanisms: in the low temperature range(67 KTρ(T) accords with the ρ-T2.5 relation, and the transport mechanism is the actions of spin wave scattering and electron-magneton scattering, while in the high temperature range(292 KTρ(T) accords with the ρ-T2 relation, and the transport mechanism is single magneton scattering.