Wanwoo Noh

EECS Department, University of California, Berkeley

Technical Report No. UCB/EECS-2022-111

May 13, 2022

http://www2.eecs.berkeley.edu/Pubs/TechRpts/2022/EECS-2022-111.pdf

Semiconductor lasers based on microcavities have attracted a large amount of interest owing to their potential as highly integrated components in photonic circuits as well as diverse applications. Especially, it has been challenging for different types of cavities to operate under single-mode operation and to lase in a preselected mode. In this talk, We report novel ways to preselect and maintain single-mode lasing in cavities of different dimensionalities. First, we demonstrate subwavelength (0D) microdisk resonators connecting bridges and propose a novel method using the number and symmetry of bridges to enhance or reduce wave confinement in the whispering gallery cavity. Second, we report single-mode lasing of valley-Hall ring cavities using the interface (1D) between two topologically distinct photonic crystals. We will present that the degree of asymmetry governs four photon confinement regimes at the interface of topologically distinct valley-Hall domains, and, evidences an interplay between the width of the topological bandgap and the quality factor of ring-like modes for single-mode operation. Finally, we will demonstrate a single-mode lasing cavity based on the 2D photonic crystal array. Carefully tuned photonic crystal design shows infinitely scalable cavities while operating under single-mode, resolving a longstanding question in the field for several decades. Our results open the door to novel optoelectronic devices and systems based on compact integrated circuits.

Advisors: Boubacar Kanté

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BibTeX citation:

@phdthesis{Noh:EECS-2022-111,
    Author= {Noh, Wanwoo},
    Title= {Single-Mode Lasing in Cavities of Different Dimensionalities},
    School= {EECS Department, University of California, Berkeley},
    Year= {2022},
    Month= {May},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2022/EECS-2022-111.html},
    Number= {UCB/EECS-2022-111},
    Abstract= {Semiconductor lasers based on microcavities have attracted a large amount of interest owing to their potential as highly integrated components in photonic circuits as well as diverse applications. Especially, it has been challenging for different types of cavities to operate under single-mode operation and to lase in a preselected mode. In this talk, We report novel ways to preselect and maintain single-mode lasing in cavities of different dimensionalities. First, we demonstrate subwavelength (0D) microdisk resonators connecting bridges and propose a novel method using the number and symmetry of bridges to enhance or reduce wave confinement in the whispering gallery cavity. Second, we report single-mode lasing of valley-Hall ring cavities using the interface (1D) between two topologically distinct photonic crystals. We will present that the degree of asymmetry governs four photon confinement regimes at the interface of topologically distinct valley-Hall domains, and, evidences an interplay between the width of the topological bandgap and the quality factor of ring-like modes for single-mode operation. Finally, we will demonstrate a single-mode lasing cavity based on the 2D photonic crystal array. Carefully tuned photonic crystal design shows infinitely scalable cavities while operating under single-mode, resolving a longstanding question in the field for several decades. Our results open the door to novel optoelectronic devices and systems based on compact integrated circuits.},
}

EndNote citation:

%0 Thesis
%A Noh, Wanwoo 
%T Single-Mode Lasing in Cavities of Different Dimensionalities
%I EECS Department, University of California, Berkeley
%D 2022
%8 May 13
%@ UCB/EECS-2022-111
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/2022/EECS-2022-111.html
%F Noh:EECS-2022-111