Long wavelength interdomain phonons and instability of dislocations in small-angle twisted bilayers
arXiv:2409.04166 · doi:10.1088/2053-1583/adac6f
Abstract
We develop a theory for long wavelength phonons originating at dislocations separating domains in small-angle twisted homobilayers of 2D materials such as graphene and MX transition metal dichalcogenides (M=Mo,W; X=S,Se). We find that both partial and perfect dislocations, forming due to lattice relaxation in the twisted bilayers with parallel and anti-parallel alignment of unit cells of the constituent layers, respectively, support several one-dimensional subbands of the {\it interdomain} phonons. We show that spectrum of the lowest gapless subband is characterized by imaginary frequencies, for wave-numbers below a critical value, dependent on the dislocation orientation, which indicates an instability for long enough straight partial and perfect dislocations. We argue that pinning potential and/or small deformations of the dislocations could stabilize the gapless phonon spectra. The other subbands are gapped, with subband bottoms lying below the frequency of interlayer shear mode in domains, which facilitates their detection with the help of optical and magnetotransport techniques.
References in corpus (47)
- Magic-angle graphene superlattices: a new platform for unconventional superconductivity
- Moire bands in twisted double-layer graphene
- Tuning superconductivity in twisted bilayer graphene
- Stacking-engineered ferroelectricity in bilayer boron nitride
- Interfacial Ferroelectricity by van-der-Waals Sliding
- The Shear Mode of Multi-Layer Graphene
- Atomic and electronic reconstruction at van der Waals interface in twisted bilayer graphene
- Interlayer breathing and shear modes in few-trilayer MoS2 and WSe2
- Moiré heterostructures as a condensed matter quantum simulator
- Strain Solitons and Topological Defects in Bilayer Graphene
- Interfacial ferroelectricity in rhombohedral-stacked bilayer transition metal dichalcogenides
- Atomic reconstruction in twisted bilayers of transition metal dichalcogenides
- Interfacial ferroelectricity in marginally twisted 2D semiconductors
- Flat bands in twisted bilayer transition metal dichalcogenides
- Charge-polarized interfacial superlattices in marginally twisted hexagonal boron nitride
- Relaxation and Domain Formation in Incommensurate 2D Heterostructures
- Atomic reconstruction and moiré patterns in transition metal dichalcogenide van der Waals heterostructures
- Topologically Protected Helical States in Minimally Twisted Bilayer Graphene
- Direct imaging of topological edge states at a bilayer graphene domain wall
- Stacking domains and dislocation networks in marginally twisted bilayers of transition metal dichalcogenides
- -Valley Transition-Metal-Dichalcogenide Moirè Bands
- Mapping of Low-Frequency Raman Modes in CVD-Grown Transition Metal Dichalcogenides: Layer Number, Stacking Orientation and Resonant Effects
- Strain-shear coupling in bilayer MoS2
- Lattice reconstruction induced multiple ultra-flat bands in twisted bilayer WSe2
- Moiré phonons in the twisted bilayer graphene
- Origin and Evolution of Ultraflatbands in Twisted Bilayer Transition Metal Dichalcogenides: Realization of Triangular Quantum Dot Array
- Giant oscillations in a triangular network of one-dimensional states in marginally twisted graphene
- Moiré metrology of energy landscapes in van der Waals heterostructures
- Stacking boundaries and transport in bilayer graphene
- Imaging moiré deformation and dynamics in twisted bilayer graphene
- Phonons in Twisted Transition Metal Dichalcogenide Bilayers ("Twistnonics"): Ultra-soft Phasons, and a transition from Superlubric to Pinned Phase
- Moiré-pattern fluctuations and electron-phason coupling in twisted bilayer graphene
- Multifaceted moiré superlattice physics in twisted WSe bilayers
- Phonons in magic-angle twisted bilayer graphene
- Tunable spin and valley excitations of correlated insulators in -valley moiré bands
- Commensurate-incommensurate phase transition and a network of domain walls in bilayer graphene with a biaxially stretched layer
- One-dimensional proximity superconductivity in the quantum Hall regime
- Low-energy moiré phonons in twisted bilayer van der Waals heterostructures
- Giant atomic swirl in graphene bilayers with biaxial heterostrain
- Twirling and spontaneous symmetry breaking of domain wall networks in lattice-reconstructed heterostructures of 2D materials
- A topologically-derived dislocation theory for twist and stretch moiré superlattices in bilayer graphene
- Full Slonczewski-Weiss-McClure parametrization of few-layer twistronic graphene
- Moiré phonons and impact of electronic symmetry breaking in twisted trilayer graphene
- Flat-band optical phonons in twisted bilayer graphene
- Stacking domain morphology in epitaxial graphene on silicon carbide
- Dislocations in twistronic heterostructures
- Non-chiral one-dimensional states propagating inside AB/BA domain walls in bilayer graphene