Contrary to what one might imagine, objects of macroscopic size can adopt quantum behavior, coexisting in several states simultaneously. This phenomenon, which contradicts our usual perception of solids, allows us to observe novel aspects of matter.
Researchers from the University of Vienna and the University of Duisburg-Essen conducted an experiment with sodium metal nanoparticles containing thousands of atoms. Using laser beams, they placed these clusters in a quantum state where their position is not defined, enabling the observation of this matter in a wave-like state.
The MUSCLE experiment at the University of Vienna, where the quantum interference of massive nanoparticles was detected.
Credit: S. Pedalino / Uni Wien
This experiment, published in
Nature, demonstrates that the objects thus constructed, about 8 nanometers in diameter, produce clear interference patterns when they pass through an experimental device. These results confirm that quantum mechanics applies at scales where it was thought not to be present, without resorting to alternative models.
The device, called MUSCLE, uses three laser diffraction gratings to create quantum superpositions. Each nanoparticle was then passed through several paths simultaneously, generating interference fringes that match theoretical predictions. Thus, each of these objects of several thousand atoms can be in several places at the same time, in a state similar to that of the famous Schrödinger's cat.
The team achieved a macroscopic value of μ = 15.5, about ten times higher than previous experiments. The researchers plan to study even larger objects, enabling tests of quantum theories and potential applications in nanotechnology.