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D. Varshney N. Kaurav 《The European Physical Journal B - Condensed Matter and Complex Systems》2004,40(2):129-136
The temperature-dependent resistivity of the perovskite manganites La1-x
Ca
x
MnO3, with x = 0.33, is theoretically analysed within the framework of the classical electron-phonon model of resistivity, i.e., the Bloch-Gruneisen model. Due to inherent acoustic (low-frequency) phonons (
as well as high-frequency optical phonons (
, the contributions to the resistivity have first been estimated. The acoustic phonons of the oxygen-breathing mode yield a relatively larger contribution to the resistivity compared to the contribution of optical phonons. Furthermore, the nature of phonons changes around T = 167 K exhibiting a crossover from an acoustic to optical phonon regime with elevated temperature. The contribution to resistivity estimated by considering both phonons, i.e.
and
, when subtracted from thin film data, infers a power temperature dependence over most of the temperature range. The quadratic temperature dependence of
is understood in terms of electron-electron scattering. Moreover, in the higher temperature limit, the difference can be varies linearly with T
4.5 in accordance with the electron-magnon scattering in the double exchange process. Within the proposed scheme, the present numerical analysis of temperature dependent resistivity shows similar results as those revealed by experiment.Received: 8 April 2004, Published online: 12 August 2004PACS:
5.47.Gk Colossal magnetoresistance - 72.15.-v Electronic conduction in metals and alloys - 74.25.Kc Phonons - 75.30.Ds Spin wavesD. Varshney: dvboson.sop@dauniv.ac.in 相似文献
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A. B. Kaidalov 《JETP Letters》2003,77(7):349-352
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