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Imaging the itinerant-to-localized transmutation of electrons across the metal-to-insulator transition in V2O3

ABSTRACT: Description This work shows how itinerant electrons localize due to increased interactions across the Mott metal-insulator transition. In solids, strong repulsion between electrons can inhibit their movement and result in a “Mott” metal-to-insulator transition (MIT), a fundamental phenomenon whose understanding has remained a challenge for over 50 years. A key issue is how the wave-like itinerant electrons change into a localized-like state due to increased interactions. However, observing the MIT in terms of the energy- and momentum-resolved electronic structure of the system, the only direct way to probe both itinerant and localized states, has been elusive. Here we show, using angle-resolved photoemission spectroscopy (ARPES), that in V2O3, the temperature-induced MIT is characterized by the progressive disappearance of its itinerant conduction band, without any change in its energy-momentum dispersion, and the simultaneous shift to larger binding energies of a quasi-localized state initially located near the Fermi level.

SUBMITTER: Thees M

PROVIDER: S-EPMC8565841 | biostudies-literature |

REPOSITORIES: biostudies-literature

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