Bozhi Yin

EECS Department, University of California, Berkeley

Technical Report No. UCB/

May 1, 2024

http://www2.eecs.berkeley.edu/Pubs/TechRpts/Hold/1e7e61c1b06387d5de943b10435737a7.pdf

High-bandwidth density and energy-efficient readout interfaces connecting the superconductor electronic (SCE) integrated circuits (IC) with room-temperature environments are essential for emerging quantum and classical superconducting computing applications, which motivate the design of cryogenic optical links.

This work addresses four challenges in this communication link. First, a comprehensive link model, which consists of superconductor and semiconductor electronic/photonic components, is built to analyze the performance and energy efficiency of the link. Then, a novel cryogenic optical link based on the monolithic silicon photonic process and laser-forwarded coherent architecture is proposed to balance power consumption at cryogenic and room-temperature environments and improve overall energy efficiency. Next, an accurate device model is necessary for circuit design nowadays, while little is known about the transistor's behavior at cryogenic temperatures. A detailed theoretic analysis and device characterization of transistors from monolithic silicon photonic processes is presented. Following that, a proof-of-concept single-chip CMOS electronic-photonic cryogenic transmitter is designed and implemented in the 45RFSOI process. The link experiment at cryogenic temperatures with the direct drive from superconductor IC demonstrates its function, performance, and energy efficiency. Compared to the existing solution, our work shows the best energy efficiency by eliminating the extra discrete cryogenic amplifier requirement. Finally, a new type of EOPLL, including a boundless phase shifter-based phase rotator and dLev comparator-based phase estimator, is proposed to solve the inevitable time-varying phase offset issue in the laser-forwarded coherent architecture. A proof-of-concept coherent receiver with proposed EOPLL is designed and implemented in the 45SPCLO process.

Advisors: Vladimir Stojanovic

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BibTeX citation:

@phdthesis{Yin:31293,
    Author= {Yin, Bozhi},
    Editor= {Stojanovic, Vladimir},
    Title= {Cryogenic Optical Link: Device, Circuit, and System},
    School= {EECS Department, University of California, Berkeley},
    Year= {2024},
    Number= {UCB/},
    Abstract= {High-bandwidth density and energy-efficient readout interfaces connecting the superconductor electronic (SCE) integrated circuits (IC) with room-temperature environments are essential for emerging quantum and classical superconducting computing applications, which motivate the design of cryogenic optical links. 

This work addresses four challenges in this communication link. First, a comprehensive link model, which consists of superconductor and semiconductor electronic/photonic components, is built to analyze the performance and energy efficiency of the link. Then, a novel cryogenic optical link based on the monolithic silicon photonic process and laser-forwarded coherent architecture is proposed to balance power consumption at cryogenic and room-temperature environments and improve overall energy efficiency. Next, an accurate device model is necessary for circuit design nowadays, while little is known about the transistor's behavior at cryogenic temperatures. A detailed theoretic analysis and device characterization of transistors from monolithic silicon photonic processes is presented. Following that, a proof-of-concept single-chip CMOS electronic-photonic cryogenic transmitter is designed and implemented in the 45RFSOI process. The link experiment at cryogenic temperatures with the direct drive from superconductor IC demonstrates its function, performance, and energy efficiency. Compared to the existing solution, our work shows the best energy efficiency by eliminating the extra discrete cryogenic amplifier requirement. Finally, a new type of EOPLL, including a boundless phase shifter-based phase rotator and dLev comparator-based phase estimator, is proposed to solve the inevitable time-varying phase offset issue in the laser-forwarded coherent architecture. A proof-of-concept coherent receiver with proposed EOPLL is designed and implemented in the 45SPCLO process.},
}

EndNote citation:

%0 Thesis
%A Yin, Bozhi 
%E Stojanovic, Vladimir 
%T Cryogenic Optical Link: Device, Circuit, and System
%I EECS Department, University of California, Berkeley
%D 2024
%8 May 1
%@ UCB/
%F Yin:31293