  The realization of topological insulators induced by correlation effects is
one of the main issues of modern condensed matter physics. An intriguing
example of the correlated topological insulators is a magnetic Chern insulator
induced by a noncoplanar multiple-Q magnetic order. Although the realization of
the magnetic Chern insulator has been studied in the classical limit of the
Kondo lattice model, research on the magnetic Chern insulator in the original
Kondo lattice model is limited. Here, we investigate the possibility of the
many-body Chern insulator with the noncoplanar triple-Q magnetic order in the
Kondo lattice model on a triangular lattice. Using the many-variable
variational Monte Carlo method, we reveal that the triple-Q magnetic order
becomes a ground state at quarter filling in an intermediate Kondo coupling
region. We also show that the many-body Chern number is quantized to one in the
triple-Q magnetic ordered phase utilizing the polarization operators. Our
results provide a pathway for the realization of the many-body Chern insulator
in correlated electron systems.
