Metastability of quantum states is rare and still poorly understood posing a significant exprimental and theoretical challenge. In a paper just published in Nature Communications by Anže Mraz and co‑workers from the group of Dragan Mihailovic from the Jožef Stefan Institute in collaboration with with the Electrotechnical Faculty at the University of Ljubljana succeeded in visualising the microscopic dynamics of electrons in the metastable state of 1T‑TaS₂. Using a specially built low-temperature multiple-tip scanning tunnelling microscope they show that injected electrons form topological networks which cannot easily decay in order to return to the ground states. Surprisingly, the effective charge of the electrons is no longer integer, but takes on fractional values such as 13/10, 23/40 and 3611/5000. The number of such fractional states is large, but finite. The possibility of manipulating such topologically entangled networks with electrical current from an external circuit shows the way forward in the search for elusive metastable states in quantum many body systems, as well new quantum devices for quantum computation.
You can read the article here: https://www.nature.com/articles/s41467-023-43800-3