Probing electron-electron interactions in multilayer epitaxial graphene grown on SiC using temperature-dependent Hall slope

We have studied electron-electron (e-e) interactions in multilayer graphene grown on SiC(0001). We find that the observed logarithmic temperature (ln T) dependence of the Hall slope is a good physical quantity for probing e-e interactions since it is not affected by electron-phonon scattering at high temperatures. By subtracting the weak localization correction term, we are able to study e-e interactions independently. It is found that the interaction correction terms determined by two methods, which both show ln T dependences, agree better with each other in the high-temperature regime. Our approach is applicable to other two-dimensional materials which do not have buckled structures.