Save the date: sun, sea & science, where wave–particle duality means talks in the morning, surf in the afternoon. Quantum at the Dunes (IIP, Natal 🇧🇷) — School 23–27 Feb 2026 → Workshop 2–6 Mar 2026. www.even3.com.br/quantum-at-t...

Posted a joint work with Naoto Shiraishi on quantum thermodynamics. We managed to characterize the state transformability (for general coherent states!) with a correlated catalyst by the single free energy ordering. arxiv.org/abs/2510.05642

Quantum metrology in the finite-sample regime

journals.aps.org/prxquantum/a...

We propose an operational framework of #quantummetrology in the practically meaningful regime of a few measurement samples, introducing probably approximately correct (#PAC) metrology.

Our tutorial "A friendly guide to exorcising Maxwell's demon" (journals.aps.org/prxquantum/p...) is out!

The big question after the tutorial is whether I’m finally done drawing demons?

When I grow up I wanna be like Kristian: talk about quantum gravity while wearing a black-flag t-shirt.

(arxiv.org/abs/2503.03585)

Whether or not you're a fan of thermal operations, there's something fundamentally special about them: by pinning down what it means to equilibrate, thermal operations uniquely emerge! With this, we also uncover nice hierarchy of unital channels, in contrast with the classical Birkhoff theorem.

Back in Krakow after 1.5 years. First stop: my old office (just had to see it). Somehow got in and boom 💥: everything was exactly the same: Kamil’s notes on my desk, unfinished (now finished) calcs from Marti’s project, old running gear, and the cactus I bought when I started my PhD!

(1/n) Today on the arXiv, we examine the folklore that cooling a quantum system with access to another requires one to order their joint state eigenvalues in decreasing order and find that this sorting is actually dictated by a simple set of inequalities.

scirate.com/arxiv/2506.1...

New paper today! Very excited to announce we obtain, from first principles, a quantum master equation that both applies in the many-body regime and provably converges to the exact Gibbs state: arxiv.org/abs/2505.20064

Our paper (w/ Marek, @ryujitakagi.bsky.social, @nellynghy.bsky.social ) on Quantum Dynamic Programming has recently been published in PRL: journals.aps.org/prl/abstract...

Xin Yi from CQT wrote a great highlight article for this paper: www.cqt.sg/highlight/20...

Started reading “the physics of filter coffee” by @jgagneastrocoffee.bsky.social —highly recommend! While browsing around, I found out he also developed an app to measure grind size distribution. Super useful—I’ve always found it hard to get clear grind size advice or compare grinders properly.

I've been revamping and updating my collection of selected references to topics in quantum information on my homepage.

Comments, feedback and suggestions welcome!

felixleditzky.info/selected_ref...

Wrote up a little tutorial + review on higher-order quantum operations. If you love quantum channels, you can think of these as linear maps that act on channels themselves in manner fully consistent with quantum theory! I hope it helps future students / researchers! 🤗
arxiv.org/abs/2503.09693

Maxwell’s demon was on holiday, just catching up on recent updates… until it thought, ‘Hmmm, I should write a tutorial!'

Very happy to share "a friendly guide to exorcising Maxwell's demon" (arxiv.org/pdf/2503.07740).

We have a new paper 🎉: The large-scale structure of entanglement in quantum many-body systems

Thanks to @lvanluijk.bsky.social and @stotti-alex.bsky.social for the great collaboration.

arxiv.org/abs/2503.03833

Short thread below 👇 (1/n)

#entanglement #quantum #quantuminformation

Had to say goodbye to my usual Maxwell’s demon for a talk that I’m preparing (not about quantum thermo this time)… but fear not! A unitary transformation later, and voilà—a Gaussian ghost appears to say thanks instead!

A novel method detects quantum properties by observing heat flow, linking thermodynamics with quantum information theory, offering an alternative to traditional measurement techniques. doi.org/g86pcf

(1/n) Been taking sm time off that's so far included, snow hiking, dog running and espresso machine cloning.

Now headed to Copenhagen by train for long runs w @itsmealeale.bsky.social

En route I'm reading thought provoking essays and articles that force you to take a step back

Commentary below 👇

Hi all,

I was uncertain about joining a new social media, but after seeing so many great “tweets” from quantum people, I decided to give it a shot!

Below is a gif I made a few months ago while bored—just something to catch your attention.