  We have investigated magnetotransport properties of YRh6Ge4, which was
recently predicted to be a triply degenerate nodal semimetal. We find it
exhibits remarkable signatures of a chiral anomaly, manifested by large
negative longitudinal magnetoresistance, quadratic field dependence of
magnetoconductance and planar Hall effect. Furthermore, we have also observed
Shubnikov-de Haas (SdH) quantum oscillations in the magnetoresistivity
measurements on this material. The analyses of the SdH data reveal two
point-like Fermi surfaces and these pockets are found to host nearly massless
fermions. The small size of these Fermi pockets is in a good agreement with the
theoretical prediction that the triply degenerate point in YRh6Ge4 is much
closer to the Fermi level than previously demonstrated triply degenerate nodal
semimetals such as MoP and WC. These results suggest YRh6Ge4 may serve as a
model system to probe exotic properties of three-component fermions and
understand their underlying physics.
