English
Related papers

Related papers: Phonons in single and few-layer MoS2 and WS2

200 papers

For conventional materials, the thermal conductivity of thin film is usually suppressed when the thickness decreases due to phonon-boundary scattering. However, this is not necessarily true for the van der Waals solids if the thickness is…

Materials Science · Physics 2016-03-01 Xiaokun Gu , Baowen Li , Ronggui Yang

We report first-principles calculations of the structural and vibrational properties of the synthesized two-dimensional van der Waals heterostructures formed by single-layers dichalcogenides MoSe2 and WSe2. We show that, when combining…

Materials Science · Physics 2022-01-26 F. Mahrouche , K. Rezouali , F. Zaabar , A. Molina-Sánchez

We report on a Raman scattering investigation of the charge-density-wave (CDW), quasi two-dimensional rare-earth tri-tellurides $R$Te$_3$ ($R$= La, Ce, Pr, Nd, Sm, Gd and Dy) at ambient pressure, and of LaTe$_3$ and CeTe$_3$ under…

Strongly Correlated Electrons · Physics 2015-05-13 M. Lavagnini , M. Baldini , A. Sacchetti , D. Di Castro , B. Delley , R. Monnier , J. -H. Chu , N. Ru , I. R. Fisher , P. Postorino , L. Degiorgi

We measure the oscillations of a standing wave of phonons in a Bose-Einstein condensate, thus obtaining the dispersion relation. We present the technique of short Bragg pulses, which stimulates the standing wave. The subsequent oscillations…

Quantum Gases · Physics 2012-12-18 I. Shammass , S. Rinott , A. Berkovitz , R. Schley , J. Steinhauer

A self-consistent scheme for the calculations of the interacting groundstate and the near bandgap optical spectra of mono- and multilayer transition-metal-dichalcogenide systems is presented. The approach combines a dielectric model for the…

Mesoscale and Nanoscale Physics · Physics 2018-01-24 Lars Meckbach , Tineke Stroucken , Stephan W. Koch

We report the first Raman scattering measurements of BaC$_6$, SrC$_6$, and YbC$_6$, which along with new data on CaC$_6$, permits a systematic study of the phonons and the electron-phonon interaction within the doped graphene layers of…

Strongly Correlated Electrons · Physics 2010-06-08 Mark P. M. Dean , Christopher A. Howard , Siddharth S. Saxena , Mark Ellerby

We used Raman scattering for study the phonon modes of self-organized Ge/Si quantum dots, grown by a molecular-beam epitaxy method. It is revealed, that Ge-Ge and Si-Ge vibrational modes considerably intensify at excitation of exciton…

Mesoscale and Nanoscale Physics · Physics 2011-05-17 I. V. Kucherenko , V. S. Vinogradov , N. N. Melnik , L. V. Arapkina , V. A. Chapnin , K. V. Chizh , V. A. Yuryev

Reflectance and magneto-reflectance experiments together with theoretical modelling based on the $\mathbf{k\cdot p}$ approach have been employed to study the evolution of direct bandgap excitons in MoS$_2$ layers with a thickness ranging…

Mesoscale and Nanoscale Physics · Physics 2019-03-01 A. O. Slobodeniuk , Ł. Bala , M. Koperski , M. R. Molas , P. Kossacki , K. Nogajewski , M. Bartos , K. Watanabe , T. Taniguchi , C. Faugeras , M. Potemski

Using non-equilibrium molecular dynamics method(NEMD), we have found that the thermal conductivity of multilayer graphene nanoribbons monotonously decreases with the increase of the number of layers, such behavior can be attributed to the…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Hai-Yuan Cao , Zhi-Xin Guo , Hongjun Xiang , Xin-Gao Gong

We present a comprehensive optical study of thin films of tungsten disulfide (WS$_2$) with layer thicknesses ranging from mono- to octalayer and in the bulk limit. It is shown that the optical band-gap absorption of monolayer WS$_2$ is…

Mesoscale and Nanoscale Physics · Physics 2017-09-19 Maciej R. Molas , Karol Nogajewski , Artur O. Slobodeniuk , Johannes Binder , Miroslav Bartos , Marek Potemski

Density functional theory based calculations and experimental analysis on a limited number of real samples are performed to study how the presence of silver intercalated in the van der Waals gap of few-layer MoS$_2$ affects the…

Collective excitations of coupled electron-phonon systems are calculated for both monolayer and bilayer graphene, taking into account the non-perturbative Coulomb coupling between electronic excitations in graphene and the substrate…

Mesoscale and Nanoscale Physics · Physics 2010-11-12 E. H. Hwang , Rajdeep Sensarma , S. Das Sarma

Charge density wave (CDW) is a periodic modulation of electronic charge leading to a reconstruction of the lattice, an emergence of zone folded mode along with collective excitations.1 Transition metal chalcogenides have shown a great…

Materials Science · Physics 2023-11-07 Divya Rawat , Juhi Pandey , Ajay Soni

We theoretically investigate multiphonons resonance Raman scattering between the Landau levels in graphene on the polar substrate using the Huang-Rhys's model. We not only present the single and multiple surface optical (SO) phonons…

Mesoscale and Nanoscale Physics · Physics 2017-12-01 Zi-Wu Wang , Zhi-Qing Li

We study Dirac plasmons and their damping in spatially separated $N$-layer graphene structures at finite doping and temperatures. The plasmon spectrum consists of one optical excitation with a square-root dispersion and $N-1$ acoustical…

Mesoscale and Nanoscale Physics · Physics 2013-02-13 J. -J. Zhu , S. M. Badalyan , F. M. Peeters

The properties of pristine, free-standing graphene monolayers prepared by mechanical exfoliation of graphite are investigated. The graphene monolayers, suspended over open trenches, are examined by means of spatially resolved Raman…

Materials Science · Physics 2009-01-08 Stephane Berciaud , Sunmin Ryu , Louis E. Brus , Tony F. Heinz

We re-examine the effect of long-range Coulomb interactions on the collective amplitude and phase modes in the incommensurate charge-density-wave ground state of quasi-one-dimensional conductors. Using an effective action approach we show…

We use density functional theory to calculate the electronic band structures, cohesive energies, phonon dispersions, and optical absorption spectra of two-dimensional In$_2$X$_2$ crystals, where X is S, Se, or Te. We identify two…

Mesoscale and Nanoscale Physics · Physics 2014-09-19 V. Zolyomi , N. D. Drummond , V. I. Fal'ko

Probing phonons, quasi-particle excitations and their coupling has enriched our understanding of these 2D materials and proved to be crucial for developing their potential applications. Here, we report comprehensive temperature, 4-330 K,…

Materials Science · Physics 2022-03-14 Deepu Kumar , Vivek Kumar , Rahul Kumar , Mahesh Kumar , Pradeep Kumar

Density functional perturbation theory is used to analyze electron-phonon interaction in bilayer graphene. The results show that phonon scattering in bilayer graphene bears more resemblance with bulk graphite than monolayer graphene. In…

Mesoscale and Nanoscale Physics · Physics 2010-11-29 K. M. Borysenko , J. T. Mullen , X. Li , Y. G. Semenov , J. M. Zavada , M. Buongiorno Nardelli , K. W. Kim