AI & ML Practical Magic

We swapped out a piece of an AI’s digital brain for actual light, which lets it think at the literal speed of optics.

April 13, 2026

Original Paper

Integrated electro-optic attention nonlinearities for transformers

Luis Mickeler, Kai Lion, Alfonso Nardi, Jost Kellner, Pierre Didier, Bhavin J. Shastri, Niao He, Rachel Grange

arXiv · 2604.09512

The Takeaway

By moving the Softmax function from digital chips to analog lithium niobate modulators, this research could radically slash the latency of AI models. It’s a major step toward hardware that computes as fast as light can travel through it.

From the abstract

Transformers have emerged as the dominant neural-network architecture, achieving state-of-the-art performance in language processing and computer vision. At the core of these models lies the attention mechanism, which requires a nonlinear, non-negative mapping using the Softmax function. However, although Softmax operations account for less than 1% of the total operation count, they can disproportionately bottleneck overall inference latency. Here, we use thin-film lithium niobate (TFLN) Mach-Ze