Nathaniel Chen

Research.

Real-time control of tokamaks — foundation models, computer vision, and signal processing for plasma state estimation and instability prediction. Advised by Egemen Kolemen at Princeton MAE / PPPL.

TokEye — fast signal extraction for fluctuating tokamak time series.

Current focus

Building foundation models for fusion: large neural networks trained on diverse tokamak data that can be specialized to downstream control and diagnostic tasks. I'm also working on real-time emission-front control and self-supervised identification of coherent modes — both run at DIII-D.

Selected experimental work

  • Led a real-time ML-enabled emission front control experiment at DIII-D (APS DPP 2024).
  • Built TokEye, a fast signal-extraction pipeline for fluctuating tokamak time series (arXiv Feb 2026).

Broader interests

  • Foundation models for scientific time-series data
  • Vision-based state estimation and active learning on streaming data
  • Uncertainty quantification when ML sits inside safety-critical control loops
  • Regulatory and compliance considerations for AI in fusion

External profiles

Google Scholar · ORCID · GitHub

Peer-reviewed

Regulation Compliant AI for Fusion
Nuclear FusionFeb 2026

Preprints & workshop papers

Towards Large-Scale Heterogeneous Data Organization for Scientific Foundation Models
ICLR 2026 Workshop DATA-FMApr 2026
TokEye: Fast Signal Extraction for Fluctuating Time Series
arXivFeb 2026
Beyond the Loss Curve: Scaling Laws, Active Learning
arXivFeb 2026
Visual Perception of 3D Space and Shape in Time
bioRxivMar 2022

Talks

Self-Supervised Identification of Coherent Modes in Tokamaks
67th Annual Meeting of the APS Division of Plasma PhysicsNov 2025
Towards a Foundation Model for Fusion
67th Annual Meeting of the APS Division of Plasma PhysicsNov 2025
Compact Experimental Negative TriAngUlarity Reactor (CENTAUR)
67th Annual Meeting of the APS Division of Plasma PhysicsNov 2025
Real-Time Machine-Learning Enabled Emission Front Control at DIII-D
66th Annual Meeting of the APS Division of Plasma PhysicsNov 2024
Investigating Guiding Center Versus Full Orbit Effects with ORBIT-GPU
64th Annual Meeting of the APS Division of Plasma PhysicsOct 2022