中文
相关论文

相关论文: Anomalous excitonic resonance Raman effects in few…

200 篇论文

The ab initio prediction of Raman intensities for bulk solids usually relies on the hypothesis that the frequency of the incident laser light is much smaller than the band gap. However, when the photon frequency is a sizeable fraction of…

材料科学 · 物理学 2015-06-17 Yannick Gillet , Matteo Giantomassi , Xavier Gonze

We report inelastic light scattering studies on Ca(Fe0.97Co0.03)2As2 in a wide spectral range of 120-5200 cm-1 from 5K to 300K, covering the tetragonal to orthorhombic structural transition as well as magnetic transition at Tsm ~ 160K. The…

超导电性 · 物理学 2014-07-11 Pradeep Kumar , D. V. S. Muthu , L. Harnagea , S. Wurmehl , B. Büchner , A. K. Sood

Few-layer graphene possesses low-energy carriers which behave as massive fermions, exhibiting intriguing properties in both transport and light scattering experiments. Lowering the excitation energy of resonance Raman spectroscopy down to…

Polarized Raman scattering has been performed on CaC6 superconductor. We identify two of the three Raman active Eg phonon modes at 440 and 1508 cm-1 expected for the R-3m space group of CaC6. These first order scattering modes appear along…

材料科学 · 物理学 2009-11-13 A. Mialitsin , J. S. Kim , R. K. Kremer , G. Blumberg

Raman scattering experiments on Na_{x}CoO_2 yH_2O single crystals show a broad electronic continuum with a pronounced peak around 100 cm-1 and a cutoff at approximately 560 cm-1over a wide range of doping levels. The electronic Raman…

强关联电子 · 物理学 2015-06-25 P. Lemmens , K. Y. Choi , V. Gnezdilov , E. Ya. Sherman , D. P. Chen , C. T. Lin , F. C. Chou , B. Keimer

The optical and vibrational properties of nanocrystalline thin films of MoS2, comprised of a mixture of edge terminated vertically aligned (ETVA) and (001)-oriented regions, on large insulating substrates are reported. From high resolution…

We investigate the experimental signatures of Raman spectroscopy of bi- and tri-magnon excitations in the distorted triangular lattice antiferromagnets alpha-LCr2O4 (L=Sr, Ca). We utilize spin wave theory to analyze the nearly 120 degree…

强关联电子 · 物理学 2023-05-23 Junli Li , Shangjian Jin , Trinanjan Datta , Dao-Xin Yao

We measure the second-harmonic (SH) response of MoS$_2$ in a broad fundamental photon energy range between 0.85 and 1.7 eV, and present a continuous SH spectrum capturing signatures of both the fundamental A and B excitons in addition to…

介观与纳米尺度物理 · 物理学 2015-10-28 Mads L. Trolle , Yao-Chung Tsao , Kjeld Pedersen , Thomas G. Pedersen

We report generation of cascaded rotational Raman scattering up to 58th orders in coherently excited CO_2 molecules. The high-order Raman scattering, which produces a quasiperiodic frequency comb with more than 600 sidebands, is obtained…

The temperature evolution of the resonant Raman scattering from high-quality bilayer 2H-MoS$_{2}$ encapsulated in hexagonal BN flakes is presented. The observed resonant Raman scattering spectrum as initiated by the laser energy of 1.96 eV,…

We have performed polarized Raman scattering measurements on WTe$_2$, for which an extremely large positive magnetoresistance has been reported recently. We observe 5 A$_1$ phonon modes and 2 A$_2$ phonon modes out of 33 Raman active modes,…

材料科学 · 物理学 2015-02-27 W. -D. Kong , S. -F. Wu , P. Richard , C. -S. Lian , J. -T. Wang , C. -L. Yang , Y. -G. Shi , H. Ding

We combine linear and non-linear optical spectroscopy at 4K with ab initio calculations to study the electronic bandstructure of MoSe2 monolayers. In 1-photon photoluminescence excitation (PLE) and reflectivity we measure a separation…

材料科学 · 物理学 2015-11-05 G. Wang , I. C. Gerber , L. Bouet , D. Lagarde , A. Balocchi , M. Vidal , E. Palleau , T. Amand , X. Marie , B. Urbaszek

Raman excitation and emission spectra for the radial breathing mode (RBM) are reported, together with a preliminary analysis. From the position of the peaks on the two-dimensional plot of excitation resonance energy against Raman shift, the…

介观与纳米尺度物理 · 物理学 2012-05-11 A. J. Ghandour , A. Sapelkin , I. Hernandez , D. J. Dunstan , I. F. Crowe , M. P. Halsall

Temperature influences the performance of two-dimensional materials in optoelectronic devices. Indeed, the optical characterization of these materials is usually realized at room temperature. Nevertheless most {\it ab-initio} studies are…

介观与纳米尺度物理 · 物理学 2016-06-06 Alejandro Molina-Sánchez , Maurizia Palummo , Andrea Marini , Ludger Wirtz

We investigate the resonant two-magnon Raman scattering in two-dimensional (2D) Mott insulators by using a half-filled 2D Hubbard model in the strong coupling limit. By performing numerical diagonalization calculations for small clusters,…

强关联电子 · 物理学 2007-05-23 T. Tohyama , H. Onodera , K. Tsutsui , S. Maekawa

We investigated interlayer phonon modes of mechanically exfoliated few-layer 2H-SnS2 samples by using room temperature low-frequency micro-Raman spectroscopy. Raman measurements were performed using laser wavelength of 441.6, 514.4, 532 and…

材料科学 · 物理学 2018-07-16 Tharith Sriv , Kangwon Kim , Hyeonsik Cheong

Phonon spectra have been investigated by micro-Raman scattering from 290 to 20K. New peaks at 500 and 674 cm-1 appear below 250K in MgB2. These peaks are explained by the Fermi resonance, where Raman-active E2g intereacts with the overtone…

超导电性 · 物理学 2007-05-23 N. Ogita , T. Kariya , K. Hiraoka , J. Nagamatsu , T. Muranaka , H. Takagiwa , J. Akimitsu , M. Udagawa

We have investigated the Raman spectrum and excitonic effects of the novel two-dimensional Ta$_2$Ni$_3$Te$_5$ structure. The monolayer is an indirect band gap semiconductor with an electronic band gap value of 0.09 eV and 0.38 eV,…

Low energy excitations in the multiferroic material TbMnO3 have been investigated by Raman spectroscopy. Our observations reveal the existence of two peaks at 30 cm-1 and 60 cm-1. They are observed in the cycloidal phase below the Curie…

强关联电子 · 物理学 2010-10-12 P. Rovillain , M. Cazayous , Y. Gallais , A. Sacuto , M-A. Measson , H. Sakata

Bound quasiparticles, negatively charged trions and neutral excitons, are associated with the direct optical transitions at the K-points of the Brillouin zone for monolayer MoS$_2$. The change in the carrier concentration, surrounding…

材料科学 · 物理学 2017-08-01 Achintya Bera , D V S Muthu , A K Sood