Thermopower of [LaNiO$_3$/LaAlO$_3$] Superlattices

Thermopower measurements for $4{\rm K}\leq {\rm T}\leq 330 {\rm K}$ will be reported for LaNiO$_3$ films and [$m$LaNiO$_3$/$n$LaAlO$_3$] superlattices ($4\leq m\leq 10$, $n=3$ are layer thicknesses in unit cells) grown on (100)-oriented LaAlO$_3$ and SrTiO$_3$ substrates. The influence of in-plane, epitaxial strain (both compressive and tensile) on the magnitude of the thermopower and its relation to changes in the electronic structure will be discussed. The possible role of phonon drag in a sharp maximum at T$\simeq 30 {\rm K}$ and the use of thermopower to distinguish correlation and disorder effects in the upturn in the low-T resistivity, will also be addressed.