Record in Quantum Macroscopicity

We were able to demonstrate the quantum wave nature of very massive objects.

• Since 2026, our MUSCLE interferometer holds the record for the most massive particle in matter-wave interference, with sodium metal clusters exceeding 175'000 Da in mass, and a macroscopicity of µ=15.4. MUSCLE is a Talbot Lau interferometer with continuous all-optical photodepletion gratings in the deep ultra-violet.
• Between 2019 and 2025 a family of functionalized oligoporphyrins held this record in our LUMI interferometer, a Kapitza-Dirac-Talbot Lau interferometer with a long base line of 2 m total. 
  These molecules were tailored and synthesized in the chemistry group around Prof. Marcel Mayor at the University of Basel.

What does macroscopicity mean, here with a value of 15.4 ?

• Simply said, if you want to exclude the existence of tiny non-linear terms in the Schrödinger equation to the same level as done here and with the same relative fringe contrast, but using electron interferometry, you would need an electron coherence time of 80 million years (!) for what we can deduce with a coherence time of 10 ms using 170 kDa massive macromolecules.