25 February 2017 VCSELs for optical communication at Fuji Xerox
Author Affiliations +
Abstract
We introduce the characteristics of vertical-cavity surface-emitting lasers (VCSELs) for use in optical communications. In the field of optical interconnections and networks, 850 nm VCSELs are key optical transmitters due to their high-speed modulation and low power consumption. One promising candidate for achieving high-speed modulations exceeding 50 Gbps is the transverse-coupled-cavity (TCC) VCSEL. In this talk, we demonstrate the characteristics of 850 nm transverse-coupled-cavity VCSELs, which helped us achieve a high 3dB modulation bandwidth (30 GHz) at 0 °C and realize eye-opening at the large-signal modulation rate of 48 Gbps. The VCSEL's epilayer structure was grown by MOCVD. The active region consists of three strained InGaAs QWs surrounded by AlGaAs barriers. The n-type and p-type DBRs are composed of AlGaAs/AlGaAs, respectively. A line-shaped H+ ion was implanted at the center of the bowtie-shaped post, dividing it into two cavities. The threshold current of the TCC VCSEL with an oxide aperture of 3.6 μm is 0.33 mA. Only the left-side cavity is pumped, while the right cavity is unpumped. The effect of modulation bandwidth enhancement was observed over a wide temperature range of 120K thanks to an optical feedback in the coupled cavities. These results show the possibility of achieving high-speed VCSELs without any temperature or bias control. We also demonstrate an ultra-compact photodetector-integrated VCSEL with two laterally-coupled cavities. An output power and a photocurrent exhibit similar tendencies under a wide range of temperature changes. This device could be also used for monitoring output power without a conventional photodetector mounted separately.
© (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Takashi Kondo, Junichiro Hayakawa, Naoki Jogan, Akemi Murakami, Jun Sakurai, Xiaodong Gu, Fumio Koyama, "VCSELs for optical communication at Fuji Xerox", Proc. SPIE 10122, Vertical-Cavity Surface-Emitting Lasers XXI, 1012203 (25 February 2017); doi: 10.1117/12.2256774; https://doi.org/10.1117/12.2256774
PROCEEDINGS
9 PAGES


SHARE
RELATED CONTENT


Back to Top