Mott transition

About: Mott transition is a research topic. Over the lifetime, 2444 publications have been published within this topic receiving 78401 citations.

Current-induced insulator-metal transition and pattern formation in an organic charge-transfer complex

Abstract: Organic molecular Mott insulators, in which carriers are localized as a result of the electron correlation, showed nonlinear electric conduction upon application of a high electric field along the molecular stacking axis. The current-driven low-resistive state of potassium 7,7,8,8-tetracyanoquinodimethanane was stabilized down to 2 kelvin, where a metallic path was visible with a microscope. The current flow caused a stripe-like periodic phase-segregation into the carrier-rich and carrier-poor regions along the current path.

Mott transition in one dimension

Abstract: I review some of the results on the Mott transition in one-dimensional systems obtained in Refs [1–3] I discuss the phase diagram and critical properties of both Mott transitions at fixed filling and upon doping, as well as the DC and AC conductivity Application of these results to organic conductors is discussed

Quantum anomalous Hall effect from intertwined moiré bands

Abstract: Electron correlation and topology are two central threads of modern condensed matter physics. Semiconductor moire materials provide a highly tunable platform for studies of electron correlation. Correlation-driven phenomena, including the Mott insulator, generalized Wigner crystals, stripe phases and continuous Mott transition, have been demonstrated. However, nontrivial band topology has remained elusive. Here we report the observation of a quantum anomalous Hall (QAH) effect in AB-stacked MoTe2/WSe2 moire heterobilayers. Unlike in the AA-stacked structures, an out-of-plane electric field controls not only the bandwidth but also the band topology by intertwining moire bands centered at different high-symmetry stacking sites. At half band filling, corresponding to one particle per moire unit cell, we observe quantized Hall resistance, h/e2 (with h and e denoting the Planck's constant and electron charge, respectively), and vanishing longitudinal resistance at zero magnetic field. The electric-field-induced topological phase transition from a Mott insulator to a QAH insulator precedes an insulator-to-metal transition; contrary to most known topological phase transitions, it is not accompanied by a bulk charge gap closure. Our study paves the path for discovery of a wealth of emergent phenomena arising from the combined influence of strong correlation and topology in semiconductor moire materials.

Magnetic Moment Collapse-Driven Mott Transition in MnO

Abstract: The metal-insulator transition in correlated electron systems, where electron states transform from itinerant to localized, has been one of the central themes of condensed matter physics for more than half a century. The persistence of this question has been a consequence both of the intricacy of the fundamental issues and the growing recognition of the complexities that arise in real materials, even when strong repulsive interactions play the primary role. The initial concept of Mott was based on the relative importance of kinetic hopping (measured by the bandwidth) and on-site repulsion of electrons. Real materials, however, have many additional degrees of freedom that, as is recently attracting note, give rise to a rich variety of scenarios for a ``Mott transition.'' Here we report results for the classic correlated insulator MnO which reproduce a simultaneous moment collapse, volume collapse, and metallization transition near the observed pressure, and identify the mechanism as collapse of the magnetic moment due to increase of crystal field splitting, rather than to variation in the bandwidth.