2026-09-23T04:32:02Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/120327 2023-09-05 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

Feng, Milton Feng, Milton Jin, Jianming Dragic, Peter D Lee, Minjoo Lawrence 2023-05 application/pdf en text Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2025-05-01 The student, Wenning Fu, accepted the attached license on 2022-12-16 at 11:51. The student, Wenning Fu, submitted this Dissertation for approval on 2022-12-16 at 12:21. This Dissertation was approved for publication on 2023-01-04 at 13:36. DSpace SAF Submission Ingestion Package generated from Vireo submission #18804 on 2023-09-01 at 17:12:16 High-speed oxide-VCSELS for optical data links in data center and cryogenic computing applications Fu, Wenning 2023-01-04 High-speed Communication Oxide Vcsels In recent years, there is a growing demand for a high-speed and power-efficient data extraction from cryogenic environments, such as superconducting processors based on single flux quantum (SFQ) technology at 4 Kelvin (K). To achieve such data transfer from 4 K to room-temperature electronics, optical data links based on cryogenic VCSELs at 4 K or an intermediate temperature are promising solutions due to low signal loss and low heat leak in fibers. The main work demonstrated in this dissertation is the development of a record high-speed cryogenic VCSEL with optical data transmission over 50 Gb/s from liquid-nitrogen and liquid-helium temperature to room-temperature electronics. Furthermore, the bandwidth measurement, microwave modeling, and parameter extraction have indicated that the capability of the cryogenic VCSELs is far beyond 50 Gb/s data rate. The extracted intrinsic bandwidth of 88.7 GHz at liquid-nitrogen temperature projects to a 200 Gb/s, sub-100 fJ/bit single-VCSEL, single-fiber data link. Also reported is the first demonstration that superconducting circuits are used to modulate a fully packaged VCSEL for up to 20 Gb/s NRZ data transmission via a fiber link from 4 K all the way to room-temperature users. The data rate is limited by the superconducting processor available to use. The authors believe that this work paves the way for next-generation cryogenic computing technologies by solving one of the key issues: the need of a high-speed, efficient, and low-heat-leak data communication between cryogenic and room-temperature environments. To make a transition into the cryogenic VCSEL development chapter, room-temperature VCSEL development, which was partially contributed by the author, is presented first. For many years, room-temperature GaAs-based 850nm VCSELs have been deployed in data centers for short-reach optical data links. However, there is a constant need to increase the link speed to accommodate the ever-growing data traffic. The dissertation will discuss operation physics, emerging challenges, and solutions in the development of VCSELs for 50 Gb/s NRZ data link over 100 meters OM4 fiber and operation up to 115 °C. Thesis eng https://hdl.handle.net/2142/120327 Copyright 2023 Wenning Fu Ph.D. Dissertation Electrical & Computer Engr University of Illinois at Urbana-Champaign Electrical & Computer Eng