Efficient method for calculating Raman spectra of solids with impurities and alloys and its application to two-dimensional transition metal dichalcogenides

Abstract

Raman spectroscopy is a widely used, powerful, and nondestructive tool for studying the vibrational properties of bulk and low-dimensional materials. Raman spectra can be simulated using first-principles methods, but due to the high computational cost calculations are usually limited only to fairly small unit cells, which makes it difficult to carry out simulations for alloys and defects. Here, we develop an efficient method for simulating Raman spectra of alloys, benchmark it against full density-functional theory calculations, and apply it to several alloys of two-dimensional transition metal dichalcogenides. In this method, the Raman tensor for the supercell mode is constructed by summing up the Raman tensors of the pristine system weighted by the projections of the supercell vibrational modes to those of the pristine system. This approach is not limited to 2D materials and should be applicable to any crystalline solids with defects and impurities. To efficiently evaluate vibrational modes of very large supercells, we adopt mass approximation, although it is limited to chemically and structurally similar atomic substitutions. To benchmark our method, we first apply it to Mo${}_x$W${}_{(1-x)}$S${}_2$ monolayer in the H-phase, where several experimental reports are available for comparison. Second, we consider Mo${}_x$W${}_{(1-x)}$Te${}_2$ in the T'-phase, which has been proposed to be 2D topological insulator, but where experimental results for the monolayer alloy are still missing. We show that the projection scheme also provides a powerful tool for analyzing the origin of the alloy Raman-active modes in terms of the parent system eigenmodes. Finally, we examine the trends in characteristic Raman signatures for dilute concentrations of impurities in MoS${}_2$.

References in corpus (25)

• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides
• Two-dimensional materials from high-throughput computational exfoliation of experimentally known compounds
• Phonons in single and few-layer MoS2 and WS2
• Phonon and Raman scattering of two-dimensional transition metal dichalcogenides from monolayer, multilayer to bulk material
• Prediction of the Weyl semimetal in the orthorhombic MoTe2
• Spectroscopic evidence for type II Weyl semimetal state in MoTe2
• Spin-orbit engineering in transition metal dichalcogenide alloy monolayers
• Quantum Spin Hall Effect in Two-dimensional Crystals of Transition Metal Dichalcogenides
• Engineering the structural and electronic phases of MoTe2 through W substitution
• Raman signatures of inversion symmetry breaking and structural phase transition in type-II Weyl semimetal MoTe2
• Raman fingerprint of semi-metal WTe2 from bulk to monolayer
• Activation of new Raman modes by inversion symmetry breaking in type II Weyl semimetal candidate T'-MoTe2
• Recovering hidden Bloch character: Unfolding Electrons, Phonons, and Slabs
• A Comprehensive Multiphonon Spectral Analysis in MoS2
• Raman scattering in transition metal dichalcogenides MTe2 (M = Mo, W)
• Raman scattering in few-layer MoTe${}_2$
• Evolution of Raman spectra in Mo${}_{1-x}$W${}_x$Te${}_2$ alloys
• Mode-decomposition based on crystallographic symmetry in the band-unfolding method
• Intrinsic Phonon Bands in High-Quality Monolayer T' Molybdenum Ditelluride
• Anisotropic Thermal Transport in Phase-Transition Layered 2D Alloys WSe2(1-x)Te2x
• A general group theoretical method to unfold band structures and its application
• Phonon Anharmonicity in Bulk $T_d$-MoTe${}_2$
• Phonon transport in single-layer Mo1-xWxS2 alloy embedded with WS2 nanodomains

Cited by in corpus (4)

• High-throughput computation of Raman spectra from first principles
• Chlorine doping of MoSe2 flakes by ion implantation
• Controlled defect production in monolayer MoS2 via electron irradiation at ultralow accelerating voltages
• Structure, Thermodynamics, and Raman Spectroscopy of Rhenium-Doped Bulk MoS${}_2$ from First Principles