Anharmonicity reveals the tunability of the charge density wave orders in monolayer VSe${}_2$

Abstract

VSe${}_2$ is a layered compound that has attracted great attention due to its proximity to a ferromagnetic state that is quenched by the presence of a charge density wave (CDW) phase. In the monolayer limit, unrelated experiments have reported different CDW orders with transition temperatures in the range of 130 to 220 K, making this monolayer very controversial. Here we perform first-principles non-perturbative anharmonic phonon calculations in monolayer VSe${}_2$ in order to estimate the CDW order and the corresponding transition temperature. Our analysis solves previous experimental contradictions as we reveal that monolayer VSe${}_2$ develops two independent charge density wave orders associated to $\sqrt{3}\times \sqrt{7}$ and $4\times 4$ modulations that compete as a function of strain. In fact, tiny variations of only 1.5% in the lattice parameter are enough to stabilize one order or the other, which underlines that the CDW order becomes substrate-dependent. The predicted CDW temperature is strain-dependent and has a value of around 220 K, in good agreement with experiments. Moreover, we analyze the impact of external Lennard-Jones interactions on the CDW. We show that these can act together with the anharmonicity to suppress the CDW orders. In the particular case of monolayer VSe${}_2$, this may give rise to the emergence of a ferromagnetic order.

arXiv comment8 pages, 4 figures, and supplemental material

References in corpus (35)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Van der Waals heterostructures
• Phonons and related properties of extended systems from density-functional perturbation theory
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Layer-dependent Ferromagnetism in a van der Waals Crystal down to the Monolayer Limit
• Discovery of intrinsic ferromagnetism in 2D van der Waals crystals
• Two-Dimensional Itinerant Ising Ferromagnetism in Atomically thin Fe3GeTe2
• Van der Waals density functional: Self-consistent potential and the nature of the van der Waals bond
• Ising-Type Magnetic Ordering in Atomically Thin FePS3
• Characterization of collective ground states in single-layer NbSe2
• Fermi surface nesting and the origin of Charge Density Waves in metals
• Anharmonic free energies and phonon dispersions from the stochastic self-consistent harmonic approximation: application to platinum and palladium hydrides
• Direct photoluminescence probing of ferromagnetism in monolayer two-dimensional CrBr3
• Evidence for a single-layer van der Waals multiferroic
• Engineering symmetry breaking in two-dimensional layered materials
• Emergence of a Metal-Insulator Transition and High Temperature Charge Density Waves in VSe2 at the Monolayer Limit
• The Stochastic Self-Consistent Harmonic Approximation: Calculating Vibrational Properties of Materials with Full Quantum and Anharmonic Effects
• Second order structural phase transitions, free energy curvature, and temperature-dependent anharmonic phonons in the self-consistent harmonic approximation: theory and stochastic implementation
• Unique gap structure and symmetry of the charge density wave in single-layer VSe${}_2$
• Emergence of charge density waves and a pseudogap in single-layer TiTe2
• Absence of ferromagnetism in VSe${}_2$ caused by its charge density wave phase
• Pressure and stress tensor of complex anharmonic crystals within the stochastic self-consistent harmonic approximation
• Quantum enhancement of charge density wave in NbS${}_2$ in the 2D limit
• Microscopic origin of multiferroic order in monolayer NiI${}_2$
• Dimensional cross-over of the charge density wave order parameter in thin exfoliated 1T-VSe${}_2$
• Weak Dimensionality Dependence and Dominant Role of Ionic Fluctuations in the Charge-Density-Wave Transition of NbSe${}_2$
• Phonon collapse and van der Waals melting of the 3D charge density wave of VSe${}_2$
• Evidence of charge density wave with anisotropic gap in monolayer VTe${}_2$ film
• Strain Engineering a $4a\times \sqrt{3}a$ Charge Density Wave Phase in Transition Metal Dichalcogenide 1T-VSe${}_2$
• Controlled Two-Dimensional Ferromagnetism in 1T-CrTe${}_2$. The role of charge density wave and strain
• Proximity-induced ferromagnetism and chemical reactivity in few layers VSe2 heterostructures
• Evidence of nodal superconductivity in monolayer 1H-TaS${}_2$ with hidden order fluctuations
• Ultrafast triggering of insulator-metal transition in two-dimensional VSe${}_2$
• Charge order from structured coupling in VSe${}_2$
• Identification of a Low Energy Metastable 1$T$-Type Phase for Monolayer VSe2

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