Optical detection of strain and doping inhomogeneities in single layer MoS{sub 2}

Journal Article · Mon Apr 25 00:00:00 EDT 2016 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4948357· OSTI ID:22591652

Michail, A.; Delikoukos, N. ^[1]; Galiotis, C. ^[2]

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1. Department of Physics, University of Patras, Patras 26504 (Greece)
2. FORTH/ICE-HT, Stadiou str Platani, Patras 26504 (Greece)

Van der Waals single-layer materials are characterized by an inherent extremely low bending rigidity and therefore are prone to nanoscale structural modifications due to substrate interactions. Such interactions can induce excess charge concentration, conformational ripples, and residual mechanical strain. In this work, we employed spatially resolved Raman and photoluminescence (PL) images to investigate strain and doping inhomogeneities in a single layer exfoliated molybdenum disulphide crystal. We have found that correlations between the spectral parameters of the most prominent Raman bands A{sub 1}′ and E′ enable us to decouple and quantify strain and charge doping effects. In comparison with Atomic Force Microscopy (AFM) topography, we show that the spatial distribution of the position of the A{sup −} -trion PL peak is strain sensitive and its linewidth can capture features smaller than the laser spot size. The presented optical analysis may have implications in the development of high-quality devices based on two-dimensional materials since structural and electronic modifications affect considerably their carrier mobility and conductivity.

• OSTI ID: 22591652
• Journal Information: Applied Physics Letters, Vol. 108, Issue 17; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATOMIC FORCE MICROSCOPY
BENDING
CARRIER MOBILITY
COMPARATIVE EVALUATIONS
CRYSTALS
EQUIPMENT
IMAGES
LASERS
LAYERS
LINE WIDTHS
MOLYBDENUM
MOLYBDENUM SULFIDES
NANOSTRUCTURES
PHOTOLUMINESCENCE
SILICON OXIDES
SPATIAL DISTRIBUTION
STRAINS
VAN DER WAALS FORCES