Condensed Matter Seminar Series

Mitali Banerjee

Laboratory of Quantum Physics: Topology and Correlations
École Polytechnique Fédérale de Lausanne

Electrons in Flatland: Strongly Correlated states of Matter

Electrons in 2D offer a huge potential for strongly correlated states when the electrons are slowed down. Not so long-ago application of high magnetic field was a popular method to ease the electrons (“flat bands”) and study the topologically protected quantum Hall states. The situation has changed after discovery of twisted bilayer graphene (TBG), which host nearly dispersion less quantum states (“flat bands”) due to moiré potential, characterized by nontrivial topology. Moiré potential profile can form flat electronic bands and manifest correlated states of electrons, where carrier doping is essential for observing those correlations. The dispersion less electrons in moiré materials demonstrate a plethora of anomalies ranging from unconventional superconductivity to giant thermopower, strange metal behavior, Fractional Chern Insulator states, among others. In this talk, I will discuss some of our efforts in understanding these correlated states.