Quantum jamming transition to a correlated electron glass in 1T-TaS2

Yaroslav A. Gerasimenko, Igor Vaskivskyi, Maksim Litskevich, Jan Ravnik, Jaka Vodeb, Michele Diego, Viktor Kabanov, Dragan Mihailovic in Nature Material, Vol. 18 Issue 8, July 2019, https://rdcu.be/bKxRq, DOI: https://www.nature.com/articles/s41563-019-0423-3

Distinct many-body states may be created under non-equilibrium conditions through different ordering paths, even when their constituents are subjected to the same fundamental interactions. The phase-transition mechanism to such states remains poorly understood. Here we show that controlled optical or electromagnetic perturbations can lead to an amorphous metastable state of strongly correlated electrons in a quasi-two-dimensional dichalcogenide. Scanning tunnelling microscopy reveals a hyperuniform pattern of localized charges, whereas multitip surface nanoscale conductivity measurements and tunnelling spectroscopy show an electronically gapless conducting state that is different from conventional Coulomb glasses and manybody localized systems. The state is stable up to room temperature and shows no signs of either local charge order or phase separation. The mechanism for its formation is attributed to a dynamical localization of electrons through mutual interactions. Theoretical calculations confirm the correlations between localized charges to be crucial for the state’s unusual stability.

Med poskusi, namenjenimi ustvarjanju novih oblik kvantnih materialov pod močno neravnovesnimi pogoji v kristalu tantalovega disulfida, je skupina raziskovalcev na Institutu »Jožef Stefan« s kratkimi laserskimi sunki ustvarila nenavadno gosto amorfno elektronsko snov, v kateri se zaradi medsebojnih interakcij elektroni zagozdijo. Odkritje spada na področje kvantne fizike in je fundamentalno pomembno, saj odpira novo področje. Razumevanje pojava predstavlja nov velik izziv za današnjo kvantno fiziko. Pojav zagozdenja elektronov lahko nastane vsepovsod tam, kjer imamo opravka s hitro kompresijo osnovnih delcev pri velikih gostotah, npr. v jedrih ali v nevtronskih zvezdah. Ima tudi potencialno uporabo, saj je pojav možno kontrolirati, ob njem pa se močno spremeni električna upornost snovi.

STA znanost, 15.7.2019: http://znanost.sta.si/2657411/slovenski-raziskovalci-odkrili-novo-zvrst-snovi-ki-je-ni-mozno-razumeti-z-obstojeco-fiziko

Dnevnik, 15.7.2019: https://www.dnevnik.si/1042892216/magazin/znanost-in-tehnologija/slovenski-raziskovalci-odkrili-novo-zvrst-snovi-ki-je-ni-mozno-razumeti-z-obstojeco-fiziko

Delo, 15.7.2019: https://www.delo.si/novice/slovenija/novo-odkritje-slovenskih-fizikov-205469.html

24ur, 15.7.2019: https://www.24ur.com/novice/znanost-in-tehnologija/nov-uspeh-slovenskih-raziskovalcev-odkrili-zvrst-ki-je-ni-moc-razumeti-z-obstojeco-fiziko.html

Scienta Omicron, 1.8.2019: https://www.scientaomicron.com/en/results/129