Fig. 2
From: Shaping the light of VCSELs through cavity geometry design
Electrical and optical characterization of VCSELs with different cavities. a Distribution of maximum optical power for different VCSEL geometries across 12 devices for each shape, with the mean (star) and median (solid line) indicated. b Bar chart comparing the averaged optical power density (mW/cm²) across the emission areas of the five cavity geometries, normalized to the optical power density of the circular (O-VCSEL) design. c Near-field patterns below the lasing threshold. d Near-field patterns at maximum power. e Simulated Q-factor distributions for the top 100 optical modes of each geometry with the standard deviation of each geometry. f Normalized Q-factors of the top 100 modes for each VCSEL geometry, sorted by decreasing Q-factor. g Averaged threshold current density for each geometry. h Averaged slope efficiency for each geometry, and the increase compared to the O-VCSEL
