Geun Ho Ahn

Geun Ho Ahn (안근호)

I am a postdoctoral researcher at Stanford University, specializing in integrated photonics, material sciences, and computational optimization to develop next generation optoelectronic systems for optical interconnects, metrology, and quantum science.

I earned my Ph.D. in Electrical Engineering from Stanford University, where I worked with Professor Jelena Vuckovic as a SGF fellow and FMA fellow on integrated photonics system through heterogeneous integration and photonic inverse design.

I completed my B.S. in EECS from UC Berkeley, where I worked with Professor Ali Javey as a Haas Scholar on optoelectronics and optical material synthesis.

I have served as a teaching assistant/co-lecturer in EE and MSE Departments at Stanford University. For this, I was awarded James F. Gibbons Award, (EE departmental teaching award).

I was born in Ulsan, South Korea, and I spent my formative years in Prague, Czechia.

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News

2026/03: Invited News and Views article on Nature Photonics
2025/08: Invited talk at SPIE Optics + Photonics, San Diego.
2025/06: Invited talk on Scalable Heterogenous Photonic Design Automation at DAC : The Chips to Systems Conference, San Francisco.
2025/04: Invited talk at Samsung Advanced Institute of Technology, Suwon, South Korea .
2025/03: Invited Department Seminar at ECE Department, Princeton University.
2024/11: Invited talk at the kick-Off event at Metapix research center, Chalmers, Sweden.
2024/10: Our work on Unified Laser Stabilizer through optical nonlinearity is published on Nature Photonics.
2024/06: Invited Summer School lecture on Photonic Inverse Design at Siegman International School on Lasers.
2024/06: I graduated from Stanford University, and was given James F. Gibbons Award at the graduation ceremony!
2024/05: Invited Special Seminar at KAIST Physics.
2024/05: Oral Presentation of our work on Unified Laser Stabilizer at CLEO 2024, Charlotte.
2023/08: Invited Symposium in Young Global Leader Symposium at KAIST Chemical & Biomolecular Engineering.
2023/03: Our waveguide integrated Te detector work is published on Optica.
2022/12: Our work on passive on-chip nonlinear optical isolators is published on Nature Photonics.

Selected Publications

	Ultrabroadband Passive Laser Noise Suppression to Quantum Noise Limit through on-chip Second Harmonic Generation Geun Ho Ahn ^†, Ziyu Wang^†, Devin J. Dean, Hubert S. Stokowski, Taewon Park, Martin M. Fejer, Jonathan Simon, Amir H. Safavi-Naeini. [^†] equal contributions. [] corresponding authors arXiv, 2026. Highly nonlinear on-chip optical conversion enables passive, ultrabroadband suppression of laser noise to the quantum-noise limit.
	High-Performance Wavelength Division Multiplexers Enabled by Co-Optimized Inverse Design Sydney Mason, Geun Ho Ahn, Jakob Grzesik, Sungjun Eun, Jelena Vučković. [] corresponding authors arXiv*, 2025. Co-Optimization on large scale photonic inverse design leads to performance breakthroughs in integrated photonic devices.
	Unified laser stabilization and isolation on a silicon chip Alexander D. White^†, , Geun Ho Ahn^†, , Richard Luhtaru, Joel Guo, Theodore J. Morin, Abhi Saxena, Lin Chang, Arka Majumdar, Kasper Van Gasse, John E. Bowers, Jelena Vučković. [^†] equal contributions. [] corresponding author Nature Photonics*, 2024. A fully passive and unified approach to simultaneously isolate and stabilize on-chip laser systems through nonlinear integrated photonics.
	Platform-agnostic waveguide integration of high-speed photodetectors with evaporated tellurium thin films Geun Ho Ahn ^†,* , Alexander D. White^†, Hyungjin Kim^†, Naoki Higashitarumizu, Felix M. Mayor, Jason F. Herrmann, Wentao Jiang, Kevin K. S. Multani, Amir H. Safavi-Naeini, Ali Javey, Jelena Vučković. [^†] equal contributions. [] corresponding author Optica*, 2023. A simple lithographically defined, thermal evaporation of semiconducting tellurium thin film allows for high-speed integrated photodetectors (> 40GHz) on novel photonic platforms that otherwise lack electrical readouts without any complex fabrication processes.
	Integrated Passive Nonlinear Optical Isolators Alexander D. White^†, , Geun Ho Ahn^†, , Kasper Van Gasse, Ki Youl Yang, Lin Chang, John E. Bowers, Jelena Vučković. [^†] equal contributions. [] corresponding author Nature Photonics*, 2022. Highlighted by Stanford News / Stanford Engineering / Phys.org / optics.org Integrated optical isolator without any external drive can be made to protect on-chip laser systems using optical nonlinear Kerr-effect in CMOS-ready thin film silicon nitride platforms
	Photonic Inverse Design of On-Chip Microresonators Geun Ho Ahn, Ki Youl Yang, Rahul Trivedi, Alexander D. White, Logan Su, Jinhie Skarda, Jelena Vučković ACS Photonics, 2022. Computational optimization aided design approach can generalize on-chip resonator design processes to enable new functionalities such as wide dispersion engineering, high optical quality factor, and more.
	Synthetic WSe₂ monolayers with high photoluminescence quantum yield Hyungjin Kim^†, Geun Ho Ahn^†, Joy Cho, Matin Amani, James P. Mastandre, Catherine K. Groschner, Der-Hsien Lien, Yingbo Zhao, Joel W. Ager III, Mary C. Scott, Daryl C. Chrzan, & Ali Javey. [^†] equal contributions. Science Advances, 2019. Large scale synthetic monolayer films can demonstrate much higher quantum yield than mechanically exfoliated counterparts, if grown properly.
	Strain-engineered growth of two-dimensional materials Geun Ho Ahn ^†, Matin Amani^†, Haider Rasool, Der-Hsien Lien, James P. Mastandrea, Joel W. Ager III, Madan Dubey, Daryl C. Chrzan, Andrew M. Minor & Ali Javey. [^†] equal contributions. Nature Communications, 2017. Highlighted by U.S. Department of Energy / Lawrence Berkeley Laboratory / phys.org Engineering the intrinsic van der waal interaction between the electronic substrate and two dimentional materials for built-in strain tunability via large scale growth.

Full Publication List on google scholar

Service

Active Reviewer in Nature Nanotechnology, Nature Photonics, ACS Photonics, Optics Express, Applied Physics Letters

EE 340: Quantum Photonics : Teaching Assistant, Spring 2024

MATSCI 199/209: Electronic and Optical Properties of Solids : Teaching Assistant, Spring 2023

EE 340: Optical Micro- and Nano-Cavities : Grader, Spring 2020

EE 222: Applied Quantum Mechanics I : Grader, Fall 2019

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