# Very high bit-rate distance product using high-power single-mode 850-nm VCSEL with discrete multitone modulation formats through OM4 multimode fiber

I. Cheng Lu, Chia Chien Wei, Hsing Yu Chen, Kuan Zhou Chen, Cheng Hsiang Huang, Kai Lun Chi, Jin Wei Shi, Fan I. Lai, Dan Hua Hsieh, Hao Chung Kuo, Wei Lin, Shi Wei Chiu, Jyehong Chen

42 引文 斯高帕斯（Scopus）

## 摘要

In order to investigate the tradeoff between optical spectral width and modulation speed of 850-nm Zn-diffusion vertical-cavity surface-emitting laser (VCSEL) and its influence on the performance of discrete multitone (DMT) modulation, two kinds of high-speed VCSEL structures with different cavity lengths (λ/2 and 3λ/2) are studied. By shortening the cavity length to λ/2, allocating the oxide layer in the standing-wave peak, and performing a Zn-diffusion aperture in our VCSEL structure, stable dual mode in the output optical spectra across the full range of bias currents with good high-speed performance (∼16-GHz bandwidth) can be achieved. Compared with its multimode reference, it shows far less roll-off with regard to the maximum data rate versus transmission distance over OM4 multimode fibers under forward error correction (FEC) threshold (BER < 3.8 \times 10-3). On the other hand, for the 3λ/2 VCSEL structure, by using the same Zn-diffusion conditions as those of dual-mode counterpart, highly single-mode operation (side-mode suppression ratio> 35 dB) with high available power can be achieved over the full range of bias currents. Although such device shows a smaller 3-dB electrical-to-optical bandwidth (12 versus 16 GHz) than that of the dual-mode one, it exhibits a superior transmission performance by use of DMT modulation format. A record high bit-rate distance product (107.6 Gb/s·km) at nearly 50-Gb/s transmission under FEC threshold (BER< 3.8 \times 10-3) through 2.2-km OM4 fibers has been successfully demonstrated by the use of single-mode VCSEL with optimized structures. In addition, error-free (BER< 1 \times 10^-12) transmission at 20.3 Gb/s with bit-rate distance product of 44.66 Gb/s·km has also been demonstrated.

原文 ???core.languages.en_GB??? 7083722 444-452 9 IEEE Journal on Selected Topics in Quantum Electronics 21 6 https://doi.org/10.1109/JSTQE.2015.2421324 已出版 - 1 11月 2015