Dear colleagues, positions at CNRS (and INRIA) will (in all probability) be announced this winter. By then it will however be too late to properly prepare an application. Recent PhDs, postdocs etc interested in such positions should get right now in contact with teams who would like to recruit them.

Looking for a postdoc to work on bosonic quantum error correction!
Join me and the QAT team at ENS & INRIA Paris — flexible start date.
Details here 👉 recrutement.inria.fr/public/class... or feel free to reach out!

Happy to share my postdoc work—our new preprint is out! 🧬 It’s been a privilege to lead this project.

I'm immensely grateful to Anton @golobor.bsky.social for being such an inspiring and supportive supervisor. Also truly thankful to @danielgerlich.bsky.social for his guidance and collaboration.

Paul Hilaire and I are recruiting a PhD student to work on demonstrations of fault-tolerant protocols for near-term quantum hardware (photonics & cold atoms). The focus is on quantum error correction, low-overhead schemes, and actual implementation on hardware

There's still work to do for full fault-tolerant *computation*, especially logical gate implementations. But this lays an important foundation.
Comments welcome! 🙂 (4/4)

This bridges a long-standing gap: while Lloyd & Braunstein showed that universal CV gates are theoretically sufficient for quantum computing, it wasn't clear if or how they could support fault tolerance. Our results strongly suggest they can—at least for memory. (3/4)

TL;DR:
If you
1. Start from vacuum
2. Use continuous-variable gates from a Lloyd-Braunstein universal set
3. Optimize gate parameters to prepare GKP qubits
→ you can achieve error rates below the threshold for GKP-surface-code quantum memory ✅ (2/4)

New preprint out: Towards fault-tolerant quantum computation with universal continuous-variable gates → arxiv.org/abs/2506.13643
We show that universal CV gate sets can deterministically prepare GKP states good enough for a fault-tolerant memory.
Many thanks to Sheron, Giulia and Alessandro! (1/4)

8/ If you're into quantum computing, quantum optics, or fundamental questions about bosonic systems, check it out! 📄👇

🔗 arxiv.org/abs/2501.13857

Would love to hear your thoughts! #QuantumComputing #QuantumOptics #Physics

7/ Takeaway: Even though bosonic systems live in infinite dimensions, the effective descriptions we use are actually sufficient to capture their physics! 🎯

6/ Why does this matter? 🤔

✔️ Validates common modeling approaches in quantum optics & computing.

✔️ Provides a general way to engineer bosonic quantum states & gates.

✔️ Leads to an infinite-dimensional Solovay–Kitaev theorem.

5/ We tackle this question & prove two key results:

1️⃣ Any physical bosonic unitary evolution can be approximated by a finite-dimensional one.

2️⃣ Any finite-dimensional unitary evolution can be exactly generated by a Hamiltonian that's a polynomial of canonical operators.

4/ To simplify their description, we often use Hilbert space truncations or polynomial Hamiltonians. But do these approximations really capture the physics❓

3/ Bosonic systems are key to many quantum phenomena—think Hong-Ou-Mandel interference or Bose-Einstein condensation.

They also involve some continuous quantities (position, momentum etc), which require infinite dimensional spaces, making some calculations more involved.

2/ TL;DR: We consider common effective models for bosonic systems & show that such simplified approaches actually produce the correct results. ✅

1/ Thrilled to finally share results from a collaboration that began ~6 years ago with Robert I. Booth & @ulyssechabaud.bsky.social
on quantum computing in infinite dimensions! 🎉

🔗 arxiv.org/abs/2501.13857

🧵👇