  The discovery of non-magnetic extreme magnetoresistance (XMR) materials has
induced great interests because the XMR phenomenon challenges our understanding
of how a magnetic field can alter electron transport in semimetals. Among XMR
materials, the LaSb shows XMR and field-induced exotic behaviors but it seems
to lack the essentials for these properties. Here, we study the
magnetotransport properties and electronic structure of LaBi, isostructural to
LaSb. LaBi exhibits large MR as in LaSb, which can be ascribed to the nearly
compensated electron and hole with rather high mobilities. More importantly,
our analysis suggests that the XMR as well as field-induced resistivity upturn
and plateau observed in LaSb and LaBi can be well explained by the two-band
model with the compensation situation. We present the critical conditions
leading to these field-induced properties. It will contribute to understanding
the XMR phenomenon and explore novel XMR materials.
