What category split would you suggest? Quant phys / Quant info?

@dulwichquantum.bsky.social

and of course, a big thank you to our funding agencies @agencerecherche.bsky.social , @dimQuantip and host institutions @lkblab.bsky.social , @sorbonne-universite.fr ,
@cea.fr, @Alice__Bob. This work wouldn’t exist without your support!

This is a first step toward probing quantum gravity with mechanical systems. Many exciting directions ahead: stronger coupling and longer coherence time would enable ground state cooling and cat-state preparation using our qubit as quantum controller! (8/8)

Crucially, our system is massive enough (~5 ng) and coherent enough (~0.3 ms) that it approaches the regime where gravitational decoherence, as proposed by Diósi and Penrose, would become observable (t_G ~ 0.5 ms).(7/8)

This imbalance directly reflects the non-commutativity of the mechanical creation and annihilation operators. A subtle but fundamental quantum effect—now visible through repeated coupling to a genuine two-level system.(6/8)

The data reveals thermal noise (nth ≈ 47 at 10 mK), plus clear signatures of qubit-induced back-action. By preparing the qubit in |g⟩ or |e⟩, we selectively probe the absorption (n) or emission (n+1) spectrum. (5/8)

We perform a sequence of stroboscopic weak measurements: after each qubit–membrane interaction, we read out the qubit in a single shot. From this, we reconstruct the membrane's motion spectrum—phonon by phonon.(4/8)

Our solution: a heavy-fluxonium qubit with a MHz-range transition, long coherence, and fast reset. This architecture enables resonant, repeatable interactions with a 4 MHz vibrating SiN membrane, sustained over its 6 ms lifetime.(3/8)

Mechanical oscillators are promising platforms for probing quantum mechanics at macroscopic scales—but coupling them strongly and coherently to a well-controlled quantum system has been a longstanding challenge. (2/8)

These notes are amazing, just the right amount of detail and insight! Thanks!

I told Craig it was crazy how fast it was from idea to implementation, and he said it should be like like a day from idea to experiment. Old dude me, I remember when your quantum computing idea might take decades to go from your idea to maybe some sort of kinda-but-just-barely experiment.