Tyler W. Hughes

Tyler W. Hughes

Head of Photonics · Flexcompute Inc.
Differentiable Simulation Inverse Design AI for Science Agentic Workflows Physics-informed ML
3,777 Citations 23 h-index 9 1st-author papers 409 ★ ceviche 330 ★ tidy3d 189 ★ angler

I like simulating the physical world with computers and using those simulations to design and optimize useful things. My focus is differentiable simulation: writing physics solvers that can compute not just what a system does, but exactly how it responds to changes, enabling gradient-based optimization over designs with enormous numbers of parameters.

I'm currently Head of Photonics at Flexcompute Inc., where I lead a technical team building AI-driven simulation products. A major part of my focus is on the agentic entrypoints to these tools: we've built an MCP server that exposes our electromagnetic solver to AI agents, and I'm deeply involved in shaping how that gets used to solve real photonic design and optimization problems. I'm drawn to this boundary where AI learns about and reasons over the physical world, both as a way to accelerate scientific work and as a rich domain for fundamental AI research.

Earlier at Flexcompute, I was the principal developer of Tidy3D (330 ★ on GitHub), our open-source Python framework for cloud-based, GPU-accelerated electromagnetic simulation. I was in the weeds on everything: writing solver code, building and maintaining the Python client, and leading community and documentation efforts. My deepest technical contribution was making the entire simulation framework differentiable: users can now differentiate through a full 3D Maxwell's equations solve running on a cloud GPU cluster in a single adjoint pass, compatible with JAX and PyTorch, enabling large-scale gradient-based inverse design with hundreds of thousands of parameters.

Before Flexcompute, I completed my PhD in Applied Physics at Stanford, advised by Prof. Shanhui Fan. My PhD work established some deep connections between physics and computation: I showed that wave physics maps exactly to recurrent neural networks, proposed and experimentally demonstrated backpropagation implemented in light for training optical neural networks, and developed adjoint methods for electromagnetic inverse design.

I studied physics at the University of Michigan and now live in New York City. When I'm not building things I'm usually traveling, cooking, or running around Central Park. Resume here, last updated November 2025.

AI agent designing photonic component
Research Flexcompute Engineering Blog
Can AI Agents Autonomously Design Components on Photonic Chips?

AI agents equipped with an electromagnetic simulator and design rule checker tackle photonic component design — waveguide bends, crossings, splitters, and demultiplexers — through iterative simulation and optimization. Explores where agentic AI excels and where it hits the limits of parametric search.

Waveguide bend optimization evolving
Tutorial Flexcompute Engineering Blog
Designing a Photonic Chip Component with ~45 Lines of Python

A compact introduction to photonic inverse design using Tidy3D. Combining electromagnetic simulation with the adjoint method, a simple 10-iteration optimization loop discovers a waveguide bend achieving ~89% power transmission through a 90° corner.

2019 – present
Flexcompute Inc.
Head of Photonics (2025–present); Principal Scientist (2024–2025); Research Scientist (2019–2024).
Building differentiable simulation frameworks, agentic design workflows, and an MCP server connecting our electromagnetic solver to AI agents. Principal developer of Tidy3D and its adjoint-based automatic differentiation plugin.
Summer 2018
Rasa · Machine Learning Intern
Open source conversational AI. Natural language understanding.
2014 – 2019
Applied Physics PhD · Stanford University
Photonic-based machine learning hardware. Electromagnetic inverse design. Laser-driven accelerators on a chip. Advisor: Shanhui Fan
2014
Gudtech Inc. · Junior Software Engineer
Full stack development of inventory management software.
2013
National University of Singapore — Centre for Quantum Technologies
Surface ion trapping for quantum information processing. Advisor: Manas Mukherjee
2010 – 2013
University of Michigan — Optoelectronic Components and Materials
Wafer reuse for low-cost, thin-film III–V photovoltaic devices. Advisor: Stephen Forrest
2009 – 2013
University of Michigan at Ann Arbor — BS Physics
Major: Physics
First & Co-First Author
Wave physics RNN
Science Advances (2019)
Co-First Author
Wave Physics as an Analog Recurrent Neural Network
We show that wave-based physical systems map exactly to the mathematics of recurrent neural networks. Using this correspondence, wave systems can be trained to passively perform machine learning tasks on sequential data — raw audio, optical signals — using only wave propagation through a structure.
Tyler W. Hughes*, Ian A.D. Williamson*, Momchil Minkov, and Shanhui Fan
Training photonic neural networks
Optica (2018)
First Author
Training of Photonic Neural Networks through In-Situ Backpropagation and Gradient Measurement
We introduce a method for measuring adjoint sensitivity directly as an intensity measurement in a photonic device, allowing the backpropagation algorithm to be physically implemented using optical signals. This enables efficient in-situ training of artificial neural networks built from integrated photonic circuits.
Tyler W. Hughes, Momchil Minkov, Yu Shi, and Shanhui Fan
Forward-mode differentiation Maxwell
ACS Photonics (2019)
First Author
Forward-Mode Differentiation of Maxwell's Equations
Differentiating electromagnetic simulations is useful for photonic device design, optimization, and sensitivity analysis. We provide a method for computing exact derivatives of Maxwell's Equations based on forward-mode differentiation, complementing the adjoint (reverse-mode) approach.
Tyler W. Hughes, Ian A.D. Williamson, Momchil Minkov, and Shanhui Fan
Adjoint nonlinear nanophotonics
ACS Photonics (2018)
Co-First Author
Adjoint Method and Inverse Design for Nonlinear Nanophotonic Devices
We extend adjoint-based gradient computation to the frequency-domain analysis of nonlinear optical devices, enabling efficient large-scale inverse design with respect to many design degrees of freedom simultaneously. Demonstrated on photonic power switches.
Tyler W. Hughes*, Momchil Minkov*, Ian A.D. Williamson, and Shanhui Fan
Selected Collaborations
Experimental Backprop
Science (2023)
Experimentally realized in situ backpropagation for deep learning in photonic neural networks
Experimental confirmation of the in-situ optical backpropagation method I introduced theoretically in 2018. Collaborators built an integrated optical circuit implementing a photonic neural network and measured gradients of a machine learning task using interference between optical signals.
Sunil Pai, Zhanghao Sun, Tyler W. Hughes, Taewon Park, Ben Bartlett, Ian AD Williamson, Momchil Minkov, Maziyar Milanizadeh, Nathnael Abebe, Francesco Morichetti, Andrea Melloni, Shanhui Fan, Olav Solgaard, David AB Miller
Anderson localization
Nature Physics (2023)
Anderson localization of electromagnetic waves in three dimensions
In this work, we used our electromagnetic simulator to observe direct evidence of Anderson localization in 3D optical systems for the first time, settling a long-standing debate in the physics community. This work required thousands of simulations of light scattering in extremely large ensembles of random spheres to gather statistics to back up these claims.
Alexey Yamilov, Sergey E Skipetrov, Tyler W. Hughes, Momchil Minkov, Zongfu Yu, Hui Cao
More First-Author
Metalens simulation
Applied Physics Letters (2021)
First Author
A perspective on the pathway toward full wave simulation of large area metalenses
We used Tidy3D to demonstrate full-wave simulation of a metalens with a diameter of hundreds of wavelengths. We argue that brute-force full-accuracy simulation provides a viable and increasingly practical pathway toward metalens design.
Tyler W. Hughes, Momchil Minkov, Victor Liu, Zongfu Yu, Shanhui Fan
Reconfigurable photonic circuit accelerator
Physical Review Applied (2019)
First Author
Reconfigurable Photonic Circuit for Controlled Power Delivery to Laser-Driven Accelerators on a Chip
We present a system for automatic control of laser power to an accelerator on a chip using a mesh of Mach-Zehnder interferometers that can be sequentially tuned to optimize power distribution.
Tyler W. Hughes, R. Joel England, and Shanhui Fan
On-chip laser power delivery
Physical Review Applied (2018)
First Author
On-Chip Laser Power Delivery System for Dielectric Laser Accelerators
We propose an integrated dielectric waveguide system for driving particle accelerators on a chip, providing a scalable path to larger energy gains and enabling practical applications of on-chip acceleration.
Tyler W. Hughes, Si Tan, Zhexin Zhao, Neil V. Sapra, YunJo Lee, Kenneth J. Leedle, Huiyang Deng, Yu Miao, Dylan S. Black, Olav Solgaard, James S. Harris, Minghao Qi, Jelena Vuckovic, R. Joel England, Robert L. Byer, and Shanhui Fan
Dielectric laser accelerator design
Optics Express (2017)
First Author
Method for Computationally Efficient Design of Dielectric Laser Accelerator Structures
We show how to systematically inverse design a dielectric accelerator structure using the adjoint method, showing an equivalence between maximizing particle energy gain and maximizing electron radiation.
Tyler W. Hughes, Georgios Veronis, Kent Wootton, R. Joel England, and Shanhui Fan
Plasmonic circuit theory
Nano Letters (2016)
First Author
Plasmonic Circuit Theory for Multiresonant Light Funneling to a Single Spatial Location
By modeling metallic nanostructures as electronic circuits, we systematically design them to focus light at the same position for multiple independently tunable frequencies, with applications in spectroscopy and biological sensing.
Tyler W. Hughes and Shanhui Fan
More Collaborations
Parallel programming photonic network
IEEE JSTQE (2020)
Parallel programming of an arbitrary feedforward photonic network
We introduced a graph-topological approach that generalizes feedforward photonic networks, with an algorithm enabling efficient programming to implement arbitrary linear operations on demand.
Sunil Pai, Ian AD Williamson, Tyler W. Hughes, Momchil Minkov, Olav Solgaard, Shanhui Fan, David AB Miller
Inverse design photonic crystals
ACS Photonics (2020)
Inverse design of photonic crystals through automatic differentiation
We implemented guided-mode expansion using automatic differentiation and used gradient information to optimize photonic crystal dispersion and cavity quality factors.
Momchil Minkov, Ian AD Williamson, Lucio C Andreani, Dario Gerace, Beicheng Lou, Alex Y Song, Tyler W. Hughes, Shanhui Fan
Optical activation functions
Optics Express (2020)
Experimental realization of arbitrary activation functions for optical neural networks
Experimental demonstration of an on-chip electro-optic circuit realizing arbitrary nonlinear activation functions for optical neural networks.
Monireh Moayedi Pour Fard, Ian AD Williamson, Matthew Edwards, Ke Liu, Sunil Pai, Ben Bartlett, Momchil Minkov, Tyler W. Hughes, Shanhui Fan, Thien-An Nguyen
Electro-optic activation functions
IEEE JSTQE — Invited (2019)
Reprogrammable Electro-Optic Nonlinear Activation Functions for Optical Neural Networks
We propose a hybrid electro-optic circuit enabling nonlinear activation functions at low optical power, with an open-source ONN simulator demonstrating performance on standard ML tasks.
Ian A.D. Williamson, Tyler W. Hughes, Momchil Minkov, Ben Bartlett, Sunil Pai, and Shanhui Fan
Wafer recycling solar cells
Advanced Functional Materials (2014)
Non-Destructive Wafer Recycling for Low-Cost Thin-Film Flexible Optoelectronics
Demonstration of thin-film III-V device fabrication by lifting off the active region and reusing the substrate, dramatically reducing cost for high-performance photovoltaics.
Kyusang Lee, Jeramy D. Zimmerman, Tyler W. Hughes, and Stephen R. Forrest
Additional Collaborations
Active nanophotonic adjoint
Optics Express (2018)
Adjoint-Based Optimization of Active Nanophotonic Devices
We show how the adjoint method may be used to inverse design periodically modulated optical devices. Our approach is based upon the multi-frequency finite-difference frequency-domain method. As a demonstration, we numerically design and optimize a compact optical isolator.
Jiahui Wang, Yu Shi, Tyler W. Hughes, Zhexin Zhao, and Shanhui Fan
Integrated accelerator chip
IPAC (2017)
Towards a Fully Integrated Accelerator on a Chip: Dielectric Laser Acceleration (DLA) From the Source to Relativistic Electrons
We discuss steps towards building a fully functional laser-driven particle accelerator on a chip, including a systematic overview of all necessary components and recent advances.
Kent Wootton, ..., Tyler W. Hughes, et al.
Flapping wing robot solar
IEEE TAP (2014)
Flexible Antenna Integrated With an Epitaxial Lift-Off Solar Cell Array for Flapping-Wing Robots
To demonstrate the applications of lightweight, thin film optoelectronic devices, we integrate a flying robot with thin-film, III-V photovoltaics, which are used for both power and wireless communication.
Jungsuek Oh, Kyusang Lee, Tyler W. Hughes, Stephen Forrest, and Kamal Sarabandi
Frontiers in Optics (2025) Visionary Speaker
Building the future of photonic design with machine learning
UW Madison Computing in Engineering Forum (2022)
Hardware-accelerated FDTD for large-scale electrodynamics
CLEO (2019) Invited
Training of photonic neural networks through in situ backpropagation
2023 Efficient Analog Backpropagation Training Architecture for Photonic Neural Networks
2022 Simultaneous Measurements of Gradients in Optical Networks
2022 Training Wave-Based Physical Systems as Recurrent Neural Networks
2022 Systems and Methods for Activation Functions for Photonic Neural Networks
2021 Training of Photonic Neural Networks Through In Situ Backpropagation
Author
tidy3d 330 ★
GPU-accelerated 3D Maxwell's equations solver with a Python client, cloud execution, and full automatic differentiation support for gradient-based inverse design.
ceviche 409 ★
Differentiable frequency-domain electromagnetic simulation (FDFD). Computes exact gradients of Maxwell's equations via forward- and reverse-mode autodiff, compatible with JAX and autograd.
angler 189 ★
Adjoint-based inverse design tool for nonlinear nanophotonic devices. Extends the adjoint method to frequency-domain nonlinear optics for gradient-based optimization of photonic structures.
Contributor
wavetorch 541 ★
Wave-based analog recurrent neural network simulator and trainer. Implements the wave physics / RNN correspondence, enabling physical systems to be trained on sequential data tasks.
neuroptica 269 ★
Simulation framework for optical neural network hardware. Models physical imperfections in integrated photonic circuits and supports training with realistic device constraints.
rasa 21,123 ★
Open-source conversational AI framework for building NLU and dialogue systems. Implemented lookup table matching for named-entity recognition during internship (2018).
Machine Learning & AI Stanford
  • CS 229 — Machine Learning
  • CS 221 — Artificial Intelligence
  • CS 230 — Deep Learning
  • CS 20 — TensorFlow for Deep Learning Research
Mathematics & Systems Stanford
  • EE 263 — Linear Dynamical Systems
  • EE 261 — Fourier Transform & Applications
  • CS 107 — Computer Organization & Systems
Physics Michigan · Stanford
  • Quantum Mechanics (through quantum field theory I)
  • Electricity & Magnetism (graduate level)
  • Classical & Statistical Mechanics (graduate level)
Complexity & Dynamics Michigan
  • CMPLXSYS 511 — Theory of Complex Systems
  • PHYS 413 — Nonlinear Dynamics & Chaos

Open to research conversations and opportunities — feel free to reach out.