Fig. 2
From: Giant two-photon upconversion from 2D exciton in doubly-resonant plasmonic nanocavity
Amplified excitonic upconverted emission by plasmonic cavity. a Excitation power-dependent upconverted emission spectra for monolayer WS2 on Au/SiO2/Si. b Excitation power-dependent upconverted emission spectra for monolayer WS2 in the designed plasmonic cavity. c Enhanced upconverted emission spectra of monolayer WS2 in the designed plasmonic cavity at an excitation power of 2.75 mW. d Excitation power-dependent integrated upconverted emission intensity (down) and enhancement (top) for monolayer WS2 in the designed plasmonic cavity. The experimental results (scattering points) can be fitted well by the blue and red dotted lines based on the power law formula I = bPα. e Comparison of the normalized time-resolved luminescence decay for WS2 deposited on the Au film (blue) and WS2 enhanced by the nanocavity mode (red) at an emission wavelength of 620 nm
