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I measured light for ten years. Now I build AI.

  1. 2014Light
  2. 2024First AI
  3. NowAgents
  4. NextNew models
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Hello

I'm Sergio.

I grew up in Madrid, studied biochemistry and followed light to Copenhagen, Glasgow and Edinburgh, where I did a PhD on a glow so faint you count it one photon at a time. Today I build AI.

  • FIDE Master at sixteen
  • Photographer, on a Hasselblad
  • Seven half marathons
What I've done
Each dot is one photon, counted the way my PhD detectors counted them. Stay a moment and the picture sharpens. 0 photons

What I've done · 2014 – 2026

Ten years of light

In my PhD in Edinburgh and my postdoc in Barcelona I made molecules glow with pairs of photons. A pair only arrives together where the beam is squeezed into a tiny focus, so the glow stays there and nowhere else.

This is the bench. Slide the lens, turn up the laser and zoom down to the focus. Then try it again with one photon.

Two photons · 800 nm

Detector 0 photons counted

The whole bench. The lens squeezes the laser into a cuvette of dye; a detector at the side counts the glow photon by photon, and a power meter catches what passes straight through.

Light with plenty of uses

  • Photodynamic therapy
  • Deep-tissue microscopy
  • 3D printing at the micron scale
  • Switching single neurons on

The one I worked on is photodynamic therapy. A drug that does nothing in the dark gathers in a tumour; light switches it on, it turns oxygen into a poison, and the cell dies. With two photons only the focus switches it on, so the healthy tissue above is spared. Aim the light yourself at each scale, and zoom from a mouse down to the molecules.

3 cm · mouse with a tumour on its flank
A mouse with a tumour on its flank. The drug has gathered in the tumour, harmless until light switches it on.

The full story, down to counting single photons at 1270 nm →

Then, my first AI system

At Sensofar I explained instruments that measure surfaces down to the nanometre, and built an assistant that answers technical questions from the company's documents.

Qwen modelfine-tuned with LoRARAG over the documentsfrontend and backendDockerCloudflare
What I'm doing now

What I'm doing · 2026

Four projects, all running here

Argus

My assistant, on my own laptop

Jarvis keeps his notes on my machine. A small router I trained decides when a job needs a bigger model, and gets it right 98% of the time.
Lab agent

An AI agent runs my PhD experiment

A local model got my old optics bench, simulated, and a hidden answer. It planned 28 steps and found it.
llama.cpp

Where a 3-second pause came from

Jarvis kept pausing before he spoke. Eight measurements later it was one line of C++; his first word now comes in 0.7 seconds.
New models

Three ways to write an answer

A 25M-parameter model solves 85% of hard Sudoku in half a second on a laptop. Watch it race a chat model and a diffusion model.

Say hello All my work

Work with me

Say hello.

I'm looking for my next AI engineering role, and I take on consulting projects too (what I offer). I live in Barcelona and work in Spanish or English.

Roles I'm after: AI engineer, forward-deployed engineer, AI research engineer.

LinkedIn GitHub CV My story