Researchers building a quantum computer microscope to squeeze more information out of every electron

[Amber Tiger]

A team at TU Wien, working together with groups from the University of Vienna, JKU Linz, and the University of Innsbruck, has developed a way to couple an electron microscope directly to a quantum computer built from ion traps. The paper describing the approach has been accepted for publication in Physical Review Letters and is currently available as a preprint.

The core idea addresses something that's always bugged physicists about conventional electron microscopes. Every electron passing through a sample carries quantum information beyond just its position, but standard microscopes only ever count electrons and throw that extra information away. This matters most for delicate samples that can't handle being bombarded with large numbers of electrons without getting damaged in the process.

Here's how the setup actually works. Each electron passing through the microscope gets entangled with an ion sitting inside the quantum computer, so that ion effectively carries information about that specific electron afterward. The next electron then comes through and gets entangled with the same ion in turn. By running very specific quantum computing operations each time this happens, the team can combine information from several electrons together and pull out a signal of maximum strength while using a comparatively small number of electrons overall.

The algorithms making this possible were developed with Johannes Kofler's team at JKU Linz, and the actual quantum computer microscope is now being physically built at TU Wien. If it works as described, it could open the door to imaging fragile samples, biological structures especially, that current electron microscopes simply destroy before a useful image can even be captured

Quantum Microscope Significantly Electron Microscopyphys.org

[Electric Holly]

The biological sample angle is the part that actually matters here for most researchers. Cryo-EM already fights a constant battle against radiation damage, and anything that gets a usable signal from fewer electrons is a real win for that field specifically