Long-range propagation of indirect excitons in van der Waals heterostructure: $1/e$ decay distance reaches $\sim 100$ microns

A long-range propagation of indirect excitons (IXs), also known as interlayer excitons, is observed in a van der Waals MoSe$_2$/WSe$_2$ heterostructure. The $1/e$ decay distance of IX luminescence reaches $\sim 100$ $\mu$m. The long-range IX propagation is realized using an optical excitation with the energy close to the MoSe$_2$ or WSe$_2$ direct exciton energy. The range of excitation powers and temperatures for the long-range IX propagation is determined.