  We demonstrate near unity, broadband absorbing optoelectronic devices using
sub-15 nm thick transition metal dichalcogenides (TMDCs) of molybdenum and
tungsten as van der Waals semiconductor active layers. Specifically, we report
that near-unity light absorption is possible in extremely thin (< 15 nm) Van
der Waals semiconductor structures by coupling to strongly damped optical modes
of semiconductor/metal heterostructures. We further fabricate Schottky junction
devices using these highly absorbing heterostructures and characterize their
optoelectronic performance. Our work addresses one of the key criteria to
enable TMDCs as potential candidates to achieve high optoelectronic efficiency.
