Miniaturized Vertical‐Cavity Surface‐Emitting Laser Array with a Novel Electrode Design for High‐Speed, Low‐Noise, and High‐Brightness Performance

Abstract

Herein, it is shown how the novel layout and arrangement of electrodes of a vertical‐cavity surface‐emitting laser (VCSEL) array can simultaneously improve its high‐speed data transmission performance and the brightness of the output beam. In contrast to the layout of the traditional VCSEL array with its isolated mesas and a single electrode to electrical parallel arrangement of all active elements, the new inverse design can effectively reduce the pitch size between neighboring light emission apertures thereby allowing significant downscaling of the whole active area of the array and high brightness output. Moreover, there are two separate electrodes in demonstrated compact 7 × 7 VCSEL array, one for pure dc current injection and the other for large ac signal modulation. Compared with the single electrode reference device, the demonstrated array shows heavier dampening of the electrical–optical (E–O) frequency response, a wider maximum 3‐dB E–O bandwidth (17 vs 13 GHz), and a Gaussian‐like optical far‐field pattern with a higher brightness output (65.95 vs 40.8 kW cm−2 sr−1), under the same high output power (≈145 mW). The advantages of this novel VCSEL array lead to a much better quality of 32 Gbps eye‐opening with a higher brightness output.