  Influencing spectral and directional features of exciton emission
characteristics from 2D transition metal dichalcogenides by coupling it to
plasmonic nano-cavities has emerged as an important prospect in nanophotonics
of 2D materials. In this paper we experimentally study the directional
photoluminescence emission from Tungsten disulfide (WS2) monolayer sandwiched
between a single-crystalline plasmonic silver nanowire (AgNW) waveguide and a
gold (Au) mirror, thus forming an AgNW-WS2-Au cavity. By employing
polarization-resolved Fourier plane optical microscopy, we quantify the
directional emission characteristics from the distal end of the AgNW-WS2-Au
cavity. Given that our geometry simultaneously facilitates local field
enhancement and waveguiding capability, we envisage its utility in 2D
material-based, on-chip nanophotonic signal processing, including nonlinear and
quantum optical regimes.
