ELFT HÍRADÓ

[Janos Asboth <asboth.janos AT ttk.bme.hu>]

Meghívó

BME Elméleti Fizika Szeminárium,

máj. 10. péntek 10h15,

1111 Budapest, Budafoki út 8., BME F III. magasföldszint 01.,
Elméleti Fizika Tanszék szemináriumi szoba

Maxime Le Ster (University of Lodz (host: Palotás Krisztián))
Moiré plane wave expansion model for simulating STM images of
incommensurate 2D materials

Moiré systems have recently attracted a lot of attention in
condensed-matter physics following the experimental discovery of
superconductivity in twisted bilayer graphene [1]. A whole plethora of
other unique quantum phases of matter have been since explored, with most
theoretical investigations focusing on the emergence of flat bands and
correlated electronics [2]. Scanning tunneling microscopy (STM) simulations
of moiré systems have however been overlooked, despite moiré patterns
almost always arising from the pairing of two-dimensional (2D) materials
and the potential assistance that simulations could provide for scientists
investigating van der Waals heterostructures. Indeed, moiré patterns can
sometimes lead to complex STM images, especially true in the case of mixed
symmetry coupling, i.e., hexagonal-rectangular symmetry pairing [3, 4]. In
these systems, the moiré unit cell can be very large and even infinite for
the incommensurate case, excluding the application of methods based on
periodic cells, e.g., density functional theory. Other approaches are thus
required; in this talk, I will introduce a new method, the moiré plane wave
expansion model (MPWEM), to simulate STM images, which simply requires a
priori knowledge of the non-interacting STM images and a small set of
intuitive parameters [5].

[1] Y. Cao et al., Nature 556, 43-50 (2018)
[2] D. M. Kennes et al., Nat. Phys. 17, 155-163 (2021)
[3] M. Le Ster et al., Phys. Rev. B 99, 075422 (2019)
[4] M. Le Ster et al., 2D Mater. 7, 011005 (2019)
[5] M. Le Ster et al., submitted.


Minden érdeklődőt szeretettel várunk.
Asbóth János,
 szemináriumi koordinátor