Figure 2
From: Zero-dimensional polariton laser in a subwavelength grating-based vertical microcavity
Spectral properties of a 0D polariton device. (a) Spectrally resolved momentum space image of the PL from a 0D cavity, which shows discrete LP modes and an UP mode. To clearly show the UP mode, the intensity of the upper panel is magnified by 40× compared to the lower panel. The straight red line at 1.551 eV corresponds to the independently measured exciton energy. The other solid lines are the calculated dispersions of the LP, UP and uncoupled cavity. The white dashed lines and the crosses (X) mark the position of the calculated discrete LP and cavity energies, respectively. (b) Spectrally resolved momentum space images of the exciton PL, measured from the unprocessed part next to the SWG–DBR cavity. (c) Spectrally resolved real space image of the PL from the 0D cavity, showing the spatial profile of the discrete LP modes. (d–e) Reflectance spectra of the 0D cavity measured from (d) the normal direction and (e) 3.5° from the normal direction, both with an angular resolution of 0.27°. (f) Temperature dependence of the LP (stars), exciton (squares) and cavity resonances (circles). 0D, zero-dimensional; DBR, distributed Bragg reflector; LP, lower polariton; PL, photoluminescence; SWG, subwavelength grating; UP, upper polariton.
