Power, Bandwidth, and Efficiency of Single VCSELs and Small VCSEL Arrays

Single-emitter vertical-cavity surface-emitting lasers (VCSELs) and multiple-emitter VCSEL arrays designed for emission at 980 nm, and with large oxide aperture diameters (<italic>φ</italic>) from ∼10.5 to 33.5 μm and with <italic>φ</italic> of ∼7.5 μm that are configured in three-emitter and seven-emitter electrically parallel triangular and hexagonal arrays, respectively, have record bandwidths and optical output powers for VCSELs with such large cumulative emitting areas. We demonstrate room temperature (RT) maximum small-signal modulation bandwidths (<italic>f</italic>_3dBmax) of 26.6 to 18.6 GHz with corresponding continuous wave (CW) optical output powers (<italic>L</italic>) of 16.2 and 47 mW for VCSELs with <italic>φ</italic> ∼13.5 and 33.5 μm, respectively. For parallel 980 nm triple and septuple arrays with <italic>φ</italic> ∼7.5 μm for each VCSEL, we demonstrate RT <italic>f</italic>_3dBmax of 25.5 and 24.8 GHz with corresponding CW <italic>L</italic> of 22.7 and 50.1 mW, respectively. We perform a comparative analysis of the RT results, which consist of standard static light output power–current–voltage (<italic>LIV</italic>) characteristics to determine the typical VCSEL figures-of-merit including wall plug efficiency (WPE), <italic>LI</italic> slope efficiency, spectral emission versus current (<italic>I</italic>), and small-signal frequency response curves. We examine the tradeoffs in optical output power, small-signal modulation bandwidth, and WPE for the various VCSEL designs, and find that while the combination of <italic>f</italic>_3dBmax and <italic>L</italic> are record values for single VCSELs and VCSEL arrays, these parameters fall off as the cumulative VCSEL array area increases to emit higher overall optical power.