Probing the uniaxial strains in MoS${}_2$ using polarized Raman spectroscopy: A first-principles study

Abstract

Characterization of strain in two-dimensional (2D) crystals is important for understanding their properties and performance. Using first-principles calculations, we study the effects of uniaxial strain on the Raman-active modes in monolayer MoS${}_2$. We show that the in-plane $E^{\prime }$ mode at 384 cm${}^{-1}$ and the out-of-plane $A_1^{\prime }$ mode at 403 cm${}^{-1}$ can serve as fingerprints for the uniaxial strain in this 2D material. Specifically, under a uniaxial strain, the doubly degenerate $E^{\prime }$ mode splits into two non-degenerate modes: one is $E_{\parallel }^{\prime }$ mode in which atoms vibrate in parallel to the strain direction, and the other is $E_{\perp }^{\prime }$ mode in which atoms vibrate perpendicular to the strain direction. The frequency of the $E_{\parallel }^{\prime }$ mode blue-shifts for a compressive strain, but red-shifts for a tensile strain. In addition, due to the strain-induced anisotropy in the MoS${}_2$ lattice, the polarized Raman spectra of the $E_{\parallel }^{\prime }$ and $E_{\perp }^{\prime }$ modes exhibit distinct angular dependence for specific laser polarization setups, allowing for a precise determination of the direction of the uniaxial strain with respect to the crystallographic orientation. Furthermore, we find that the polarized Raman intensity of the $A_1^{\prime }$ mode also shows evident dependence on the applied strain, providing additional effective clues for determining the direction of the strain even without knowledge of the crystallographic orientation. Thus, polarized Raman spectroscopy offers an efficient non-destructive way to characterize the uniaxial strains in monolayer MoS${}_2$.

14 pages, 8 figures, submitted to PRB

References in corpus (21)

• Electric Field Effect in Atomically Thin Carbon Films
• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Phosphorene: A New 2D Material with High Carrier Mobility
• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Valley polarization in MoS2 monolayers by optical pumping
• Two-Dimensional Material Nanophotonics
• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
• Uniaxial Strain in Graphene by Raman Spectroscopy: G peak splitting, Gruneisen Parameters and Sample Orientation
• The Valley Hall Effect in MoS2 Transistors
• High Performance Single Layered WSe2 p-FETs with Chemically Doped Contacts
• Integrated Circuits Based on Bilayer MoS2 Transistors
• Electrically Tunable Excitonic Light Emitting Diodes based on Monolayer WSe2 p-n Junctions
• Tightly bound excitons in monolayer WSe2
• Electroluminescence and photocurrent generation from atomically sharp WSe2/MoS2 heterojunction p-n diodes
• Probing Excitonic Dark States in Single-layer Tungsten Disulfide
• High Mobility WSe2 p- and n-Type Field Effect Transistors Contacted by Highly Doped Graphene for Low-Resistance Contacts
• Helicity resolved Raman scattering of MoS2, MoSe2, WS2 and WSe2 atomic layers
• Observation of Low-frequency Interlayer Breathing Modes in Few-layer Black Phosphorus
• Lattice Vibrational Modes and Raman Scattering Spectra of Strained Phosphorene
• Second order resonant Raman scattering in single layer tungsten disulfide (WS${}_2$)
• Group Theory analysis of phonons in two-dimensional Transition Metal Dichalcogenides

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