Anharmonicity in Raman-active phonon modes in atomically thin MoS2
| Autor: | Nedjma Bendiab, Johann Coraux, Suman Sarkar, Vincent Bouchiat, Laëtitia Marty, Goutham Nayak, Sarthak Das, Indrajit Maity, Aveek Bid, Kausik Majumdar, Manish Jain, Julien Renard, H. L. Pradeepa |
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| Přispěvatelé: | Indian Institute of Science, Institut Néel [2016-2019] (NEEL [2016-2019]), Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Systèmes hybrides de basse dimensionnalité [2020-....] (HYBRID [2020-....]), Institut Néel [2020-....] (NEEL [2020-....]), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2020-....] (UGA [2020-....])-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2020-....] (Grenoble INP [2020-....]), Université Grenoble Alpes [2020-....] (UGA [2020-....])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2020-....] (UGA [2020-....])-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2020-....] (Grenoble INP [2020-....]), Université Grenoble Alpes [2020-....] (UGA [2020-....]), Systèmes hybrides de basse dimensionnalité [2016-2019] (HYBRID [2016-2019]), Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Systèmes hybrides de basse dimensionnalité (HYBRID), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA) |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Phonon
FOS: Physical sciences 02 engineering and technology Substrate (electronics) 01 natural sciences Condensed Matter::Materials Science Laser linewidth symbols.namesake Impurity Condensed Matter::Superconductivity Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat] 010306 general physics ComputingMilieux_MISCELLANEOUS Physics Condensed Matter - Materials Science Condensed Matter - Mesoscale and Nanoscale Physics Condensed matter physics Doping Anharmonicity Materials Science (cond-mat.mtrl-sci) 021001 nanoscience & nanotechnology Full width at half maximum symbols [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] Condensed Matter::Strongly Correlated Electrons 0210 nano-technology Raman spectroscopy |
| Zdroj: | Physical Review B Physical Review B, American Physical Society, 2020, 101 (20), ⟨10.1103/PhysRevB.101.205302⟩ Physical Review B, American Physical Society, 2020, 101 (20), pp.205302. ⟨10.1103/PhysRevB.101.205302⟩ |
| ISSN: | 2469-9950 2469-9969 |
| Popis: | Phonon-phonon anharmonic effects have a strong influence on the phonon spectrum; most prominent manifestation of these effects are the softening (shift in frequency) and broadening (change in FWHM) of the phonon modes at finite temperature. Using Raman spectroscopy, we studied the temperature dependence of the FWHM and Raman shift of ${E}_{2g}^{1}$ and ${A}_{1g}$ modes for single-layer and natural bilayer ${\mathrm{MoS}}_{2}$ over a broad range of temperatures $(8l\mathrm{T}l300\phantom{\rule{0.28em}{0ex}}\mathrm{K})$. Both the Raman shift and FWHM of these modes show linear temperature dependence for $Tg100\phantom{\rule{0.28em}{0ex}}\mathrm{K}$, whereas they become independent of temperature for $Tl100\phantom{\rule{0.28em}{0ex}}\mathrm{K}$. Using first-principles calculations, we show that three-phonon anharmonic effects intrinsic to the material can account for the observed temperature dependence of the linewidth of both the modes. It also plays an important role in determining the temperature dependence of the frequency of the Raman modes. The observed evolution of the linewidth of the ${A}_{1g}$ mode suggests that electron-phonon processes are additionally involved. From the analysis of the temperature-dependent Raman spectra of ${\mathrm{MoS}}_{2}$ on two different substrates---${\mathrm{SiO}}_{2}$ and hexagonal boron nitride---we disentangle the contributions of external stress and internal impurities to these phonon-related processes. We find that the renormalization of the phonon mode frequencies on different substrates is governed by strain and intrinsic doping. Our work establishes the role of intrinsic phonon anharmonic effects in deciding the Raman shift in ${\mathrm{MoS}}_{2}$ irrespective of substrate and layer number. |
| Databáze: | OpenAIRE |
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