Eur. Phys. J. B 40, 129-136 (2004)
https://doi.org/10.1140/epjb/e2004-00251-5

Electrical resistivity in the ferromagnetic metallic state of La-Ca-MnO₃: Role of electron-phonon interaction

School of Physics, Vigyan Bhawan, Devi Ahilya University, Khandwa Road Campus, Indore 452017, India

Corresponding authors: ^a vdinesh33@rediffmail.com dvboson.sop@dauniv.ac.in

Received: 5 February 2004
Revised: 8 April 2004
Published online: 12 August 2004

Abstract

The temperature-dependent resistivity of the perovskite manganites LaCa_xMnO₃, 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.