Fakultät für Physik und Astronomie

Physikalisches Kolloquium am 03.07.2023: „Complex Quantum Phases in Flat-Band van-der-Waals Systems: Making, Controlling and Measuring by Quantum Transport“

30.06.23 | Physikalisches Kolloquium, Veranstaltung

Am Montag, den 3. Juli 2023, um 12:00 Uhr c.t., findet der nächste Termin unseres Physikalischen Kolloquiums statt.

Referent ist Prof. Dr. Thomas Weitz (Georg-August Universität Göttingen) zum Thema „Complex quantum phases in flat-band van-der-Waals systems: Making, controlling and measuring by quantum transport.

The exchange interaction can lead to correlated states in low dimensional systems such as the graphene family. Regions of large density of states are especially prone to correlation effects. In this talk I will give an introduction into the making of flat-band-systems by Morié or electrostatic engineering. I will also discuss how to probe such states by low temperature charge transport. Finally I will discuss two of our recent experiments. First, the recently identified exchange driven quantum anomalous Hall (QAH) nu=2 state that exhibits quantized charge Hall conductance close to zero magnetic field as well as spin, valley and spin-valley anomalous quantum Hall effects and out-of-plane ferroelectricity in suspended bilayer graphene. And second our recent measurements in h-BN encapsulated Bernal bilayer graphene where we realized flat electronic bands at an electric-field tunable van-Hove-singularity and placed the Fermi level in them via electrostatic gating. In such device structures we have found indications of exotic states consistent with for example a Chern insulator finite density in the valence band.

Abstract des Vortrags von Prof. Weitz.

Die Einführung erfolgt durch Prof. Dr. Michael Scherer.

Die Fakultät lädt alle Interessierten herzlich ein. Die Veranstaltung findet im Hörsaal HNB und hybrid via Zoom statt. Vor dem Kolloquium bieten wir Ihnen Kaffee und Kekse an. Über diesen Link gelangen Sie zur Zoom-Veranstaltung (MeetingID: 632 5520 9938, Passwort: 526977). Alle Termine des Physikalischen Kolloquiums finden Sie hier.

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