Hour: From 15:00h to 16:00h
Place: Seminar Room
SEMINAR: Novel probes for the cascades in magic angle twisted bilayer graphene
Magic Angle Twisted Bilayer Graphene (TBG), two graphene layers with a relaIve twist angle ~1º, features very flat bands close to the Fermi level, which are highly suscepIble to the effects of the electronic interacIons. A plethora of correlated phenomena appear as a function of doping, temperature and magnetic field. The so-called cascades, a series of asymmetric resets in the Scanning Tunneling Microscope (STM) Spectrum and the inverse compressibility of Twisted Bilayer Graphene (TBG) around integer fillings [1], remain up to tens of Kelvin and constitute the most resilient correlated phenomena in TBG together with the resisIve states as a function of doping.
After introducing the phenomenology of the cascades, I will first show that the cascade signatures in STM, compressibility and transport experiments can be explained, within a heavy fermion description, in terms of the formaIon of local moments and heavy quasiparticles in the normal state [2,3], i.e. without the need to invoke symmetry breaking, which experimentally has been unambiguously detected only below a few kelvin. I will then introduce novel ways to probe the cascade phenomena, such as optical probes [3] and the Atomic-SET and discuss the angle dependence of this phenomenon.
Hour: From 15:00h to 16:00h
Place: Seminar Room
SEMINAR: Novel probes for the cascades in magic angle twisted bilayer graphene
Magic Angle Twisted Bilayer Graphene (TBG), two graphene layers with a relaIve twist angle ~1º, features very flat bands close to the Fermi level, which are highly suscepIble to the effects of the electronic interacIons. A plethora of correlated phenomena appear as a function of doping, temperature and magnetic field. The so-called cascades, a series of asymmetric resets in the Scanning Tunneling Microscope (STM) Spectrum and the inverse compressibility of Twisted Bilayer Graphene (TBG) around integer fillings [1], remain up to tens of Kelvin and constitute the most resilient correlated phenomena in TBG together with the resisIve states as a function of doping.
After introducing the phenomenology of the cascades, I will first show that the cascade signatures in STM, compressibility and transport experiments can be explained, within a heavy fermion description, in terms of the formaIon of local moments and heavy quasiparticles in the normal state [2,3], i.e. without the need to invoke symmetry breaking, which experimentally has been unambiguously detected only below a few kelvin. I will then introduce novel ways to probe the cascade phenomena, such as optical probes [3] and the Atomic-SET and discuss the angle dependence of this phenomenon.