Impact of Device Topology on the Performance of High-Speed 1550 nm Wafer-Fused VCSELs

作者：A. V. Babichev, S. A. Blokhin, A. G. Gladyshev, L. Ya. Karachinsky, I. I. Novikov, A. A. Blokhin, M. A. Bobrov, Yakov N. Kovach, A. G. Kuzmenkov, Vladimir Nevedomsky, N. A. Maleev, E. S. Kolodeznyi, K. O. Voropaev, Alexey Vasilyev, V. M. Ustinov, A. Yu. Egorov, Saiyi Han, Si-Cong Tian, D. Bimberg · 发表于：Photonics · 年份：2023 · DOI：10.3390/photonics10060660 · 被引用次数：11 · 研究领域：Semiconductor Lasers and Optical Devices、Photonic and Optical Devices、Semiconductor Quantum Structures and Devices

A detailed experimental analysis of the impact of device topology on the performance of 1550 nm VCSELs with an active region based on thin InGaAs/InAlGaAs quantum wells and a composite InAlGaAs buried tunnel junction is presented. The high-speed performance of the lasers with L-type device topology (with the largest double-mesa sizes) is mainly limited by electrical parasitics showing noticeable damping of the relaxation oscillations. For the S-type device topology (with the smallest double-mesa sizes), the decrease in the parasitic capacitance of the reverse-biased p+n-junction region outside the buried tunnel junction region allowed to raise the parasitic cutoff frequency up to 13–14 GHz. The key mechanism limiting the high-speed performance of such devices is thus the damping of the relaxation oscillations. VCSELs with S-type device topology demonstrate more than 13 GHz modulation bandwidth and up to 37 Gbps nonreturn-to-zero data transmission under back-to-back conditions at 20 °C.