학술논문

First Demonstration of an O-Band Coherent Link for Intra-Data Center Applications
Document Type
Periodical
Source
Journal of Lightwave Technology J. Lightwave Technol. Lightwave Technology, Journal of. 41(21):6643-6650 Nov, 2023
Subject
Communication, Networking and Broadcast Technologies
Photonics and Electrooptics
Optical switches
Phase shifters
Data centers
Bandwidth
Power demand
Phase shift keying
Optical transmitters
Coherent optical link
O-Band
silicon photonics
data center
energy-efficiency
Language
ISSN
0733-8724
1558-2213
Abstract
We report the first demonstration of a full O-band coherent link for intra-data center applications, including custom photonic and electronic integrated circuits for the transmitter and receiver. Full-link 112 Gbps (56 Gbaud QPSK) transmission is shown with $2.1\cdot 10^{-4}$ measured BER, and record baud rate 128 Gbps (64 Gbaud QPSK) transmission is shown for the stand-alone coherent transmitter. The link architecture is based on analog coherent detection (ACD), which improves power consumption substantially by performing functions in the analog domain that are normally implemented with power-hungry digital signal processing (DSP). Energy efficiency of 9.5 pJ/bit is demonstrated for the O-band coherent link, with 12.5 pJ/bit expected with next-generation circuits that include integrated optical gain. These results show the potential for next-generation data center networks based on low-power O-band coherent links.