Twist to the M-ax(is): A New Moiré Platform Based on M-Point Twisting
- 👤 Speaker: Dumitru Calugaru, Princeton and Oxford
- 📅 Date & Time: Thursday 21 November 2024, 14:00 - 15:30
- 📍 Venue: TCM Seminar Room
Abstract
We introduce a new class of moiré systems based on monolayers with triangular lattices and low-energy states at the M points of the Brillouin zone. These M-point moiré materials differ fundamentally from those derived from Γ- or K-point monolayers, featuring three time-reversal-preserving valleys connected by three-fold rotational symmetry. We propose twisted bilayers of exfoliable 1T-SnSe2 and 1T-ZrS2 as examples of this new class. Using extensive ab initio simulations, we develop continuum models and show that the M-point moiré Hamiltonians exhibit emergent momentum-space non-symmorphic symmetries and a kagome lattice in momentum space. This is the first experimentally viable realization of a projective representation of crystalline space groups in a non-magnetic system. These materials also serve as six-flavor Hubbard simulators with Mott physics, indicated by their flat Wilson loops. Additionally, non-symmorphic momentum-space symmetries make the M-point Hamiltonians quasi-one-dimensional in each valley, suggesting the potential for realizing Luttinger liquid physics. We predict the twist angles for the emergence of flat conduction bands, provide a continuum Hamiltonian, analyze its topology and charge density, and discuss aspects of the physics of this new platform.
Series This talk is part of the Theory of Condensed Matter series.
Included in Lists
- All Cavendish Laboratory Seminars
- All Talks (aka the CURE list)
- Centre for Health Leadership and Enterprise
- Combined TCM Seminars and TCM blackboard seminar listing
- Featured lists
- few29
- Lennard-Jones Centre external
- ME Seminar
- Neurons, Fake News, DNA and your iPhone: The Mathematics of Information
- PMRFPS's
- School of Physical Sciences
- TCM Seminar Room
- Theory of Condensed Matter
- Thin Film Magnetic Talks
Note: Ex-directory lists are not shown.
![[Talks.cam]](/static/images/talkslogosmall.gif)

Dumitru Calugaru, Princeton and Oxford
Thursday 21 November 2024, 14:00-15:30