Thermopower of LaFe13−xSix alloys
1 Department of Materials, Imperial College London - Exhibition Road, London, SW7 2AZ, UK, EU
2 Department of Physics, Imperial College London - Exhibition Road, London, SW7 2AZ, UK, EU
Received: 20 September 2012
Accepted: 19 November 2012
We measured the thermopower of LaFe11.6Si1.4 and its hydride LaFe11.6Si1.4Hy to investigate changes in the electronic structure induced by hydriding. Using a model based on a density-of-states (DOS) function we can accurately describe a non-linear temperature dependence of the thermopower over a wide temperature range. The fit of the model to experimental data yields a significantly broader maximum in the DOS function near the Fermi energy of the hydride as compared to LaFe11.6Si1.4. Additionally, a new scattering mechanism leading to a decreased thermopower is observed in LaFe11.6Si1.4Hy at low temperatures which is attributed to scattering of electrons on magnetic excitation.
PACS: 72.15.Jf – Thermoelectric and thermomagnetic effects / 75.10.Lp – Band and itinerant models / 75.30.Sg – Magnetocaloric effect, magnetic cooling
© EPLA, 2012