Anomalous lattice vibrations of CVD-grown monolayer MoS₂ probed using linear polarized excitation light

Abstract

Anomalous lattice vibrations are observed in CVD-grown monolayer MoS2 when rotating the sample and using the linear polarization incident light.

Recent Advances in Strain-Induced Piezoelectric and Piezoresistive Effect-Engineered 2D Semiconductors for Adaptive Electronics and Optoelectronics

“…Recently, 1825 low-exfoliation-energy materials were selected from more than 100,000 kinds of three-dimensional compounds, containing intrinsic metallic, semi-conducting, insulating and magnetic materials [7]. 2D materials have demonstrated unparalleled opportunities in science and industry and have caused great attention due to their sub-nanometer thickness, unique structure and unusual electronic properties, which provide advance in electronic [8], optoelectronic [9][10][11][12][13], ultrafast photonics [14][15][16][17][18][19], sensor [20][21][22], energy field [23][24][25][26][27][28] and biological medicine [29][30][31][32]. Some novel physical phenomena have been found and proved in 2D materials, such as Hofstadter butterfly, Ising superconductivity, valley Hall effect and valleytronics [33][34][35][36].…”

Forbidden and Second-Order Phonons in Raman Spectra of Single and Few-Layer MoS2 Close to C Exciton Resonance

“…For example, the changes in the A 1g and E 2g 1 peaks have been used to reveal the combined effects of strain and doping of MoS 2 grown on the Au substrate arising from their strong interaction with and modulated by the Au roughness . The anomalous photothermal behavior of A 1g and E 2g 1 peaks detected in chemical vapor deposition (CVD) single-layer MoS 2 has been related to the strain induced by the substrate . These peaks have also been used to compare ME and CVD (grown on SiO 2 ) samples showing that frequency differences are related to the strain induced by the substrate that is relaxed by the water film created when CVD samples are transferred …”

“…33 The anomalous photothermal behavior of A 1g and E 2g 1 peaks detected in chemical vapor deposition (CVD) single-layer MoS the strain induced by the substrate. 34 These peaks have also been used to compare ME and CVD (grown on SiO 2 ) samples showing that frequency differences are related to the strain induced by the substrate that is relaxed by the water film created when CVD samples are transferred. 20 The aim of this work is to reveal the subtle effects induced by the growth method, the substrate, and the number of layers and their correlation to the electronic structure, defects, and interaction with the substrate.…”

Effects of MoS2 Layer Thickness on Its Photochemically Driven Oxidative Dissolution

“…The first mode, A 1g (∼409 cm –1 ), was attributed to the out-of-plane vibration of S atoms; the second mode, E 1 2g (∼383 cm –1 ), was attributed to in-plane vibrations of Mo–S bonds. The nanosheets did not show any other peaks, indicating they were composed solely of the 2H phase . Interestingly, the E 1 2g peak of the nominally 18 nm thick MoS 2 nanosheets was shifted to a higher frequency (∼385 cm –1 ), narrowing the frequency difference to ∼24 cm –1 , compared to the ∼26 cm –1 value for bulk and 46 nm thick MoS 2 (inset of Figure B).…”