TY - JOUR AU - VARSHNEY, Dinesh AU - CHOUDHARY, Dinesh PY - 2014 TI - Role of phonon drag and carrier diffusion in thermoelectric power of polycrystalline La0.97Na0.03MnO3 manganites JO - Journal of Advanced Ceramics SN - 2226-4108 SP - 224 EP - 229 VL - 3 IS - 3 AB - We develop a theoretical model for quantitative analysis of temperature-dependent thermoelectric power of monovalent (Na) doped La0.97Na0.03MnO3 manganites. In the ferromagnetic regime, we have evaluated the phonon thermoelectric power by incorporating the scattering of phonons with impurities, grain boundaries, charge carriers and phonons. In doing so, we use the Mott expression to compute the carrier (hole) diffusion thermoelectric power ( Scdiff) using Fermi energy as carrier (hole)-free parameter, and Scdiff shows linear temperature dependence and phonon drag Sphdrag increases exponentially with temperature which is an artifact of various operating scattering mechanisms. It is also shown that for phonons the scattering and transport cross-sections are proportional to ω4 in the Rayleigh regime where ω is the frequency of the phonons. Numerical analysis of thermoelectric power from the present model shows similar results as those revealed from experiments. UR - https://doi.org/10.1007/s40145-014-0113-1 DO - 10.1007/s40145-014-0113-1