Berry phase and de Haas-van Alphen effect in LaRhIn5.

We explain the experimental data on the magnetization of LaRhIn5 recently published by Goodrich et al. [Phys. Rev. Lett. 89, 026401 (2002)]]. We show that the magnetization of a small electron group associated with a band-contact line was detected in that Letter. These data provide the first observation of the Berry phase of electrons in metals via the de Haas-van Alphen effect.