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Related papers: Raman phonons in ReOFeAs (Re= Sm, La)

200 papers

The temperature dependence below $T_{c}$ of the lineshape of optical phonons of different symmetry as seen in Raman scattering is investigated for superconductors with anisotropic energy gaps. It is shown that the symmetry of the…

Condensed Matter · Physics 2009-10-22 T. P. Devereaux

We report the results of polarization-dependent Raman spectroscopy of phonon states in single-crystalline quasi-one-dimensional NbTe$_4$ and TaTe$_4$ van der Waals materials. The measurements were conducted in the wide temperature range…

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…

Materials Science · Physics 2018-07-16 Tharith Sriv , Kangwon Kim , Hyeonsik Cheong

We have used Raman spectroscopy to study indium nitride thin films grown by molecular beam epitaxy on (111) silicon substrates at temperatures between 450 and 550 C. The Raman spectra show well defined peaks at 443, 475, 491, and 591…

Materials Science · Physics 2009-10-31 F. Agullo-Rueda , E. E. Mendez , N. Bojarczuk , S. Guha

We report Raman spectra and synchrotron x-ray diffraction measurements of lattice parameters of polycrystalline MgB2 under hydrostatic pressure conditions up to 15 GPa. An anomalously broadened Raman band at 620 cm-1 is observed that…

Ferroaxial order is characterized by the breaking of mirror symmetry parallel to the crystallographic principal axis, which often originates from spontaneous rotational distortions of the crystal lattice. Such rotational distortions are, by…

Chromium thiophosphate (CrPS4), a monoclinic crystal of C_2^3 space group, is a ternary layered semiconductor with an optical bandgap of 1.4 eV and exhibits antiferromagnetism below 36 K. Despite its potential in optoelectronic and magnetic…

Chemical Physics · Physics 2021-07-16 Sujin Kim , Jinhwan Lee , Changgu Lee , Sunmin Ryu

In ionic Raman scattering, infrared-active phonons mediate a scattering process that results in the creation or destruction of a Raman-active phonon. This mechanism relies on nonlinear interactions between phonons and has in recent years…

Phonon modes and their association with the electronic states have been investigated for the metallic EuCu$_{2}$As$_{2}$ system. In this work, we present the Raman spectra of this pnictide system which clearly shows the presence of seven…

Strongly Correlated Electrons · Physics 2025-01-10 Debasmita Swain , Mainak Dey Sarkar , Andrzej Ptok , G. Vaitheeswaran , Anushree Roy , Sitikantha D Das

We present evidence for a concomitant structural and ferroelectric transformation around $T_S\sim 360$ K in multiferroic BiFeO$_3$/LaAlO$_3$ thin films close to the tetragonal phase. Phonon excitations are investigated by using Raman…

Strongly Correlated Electrons · Physics 2015-05-30 K. -Y. Choi , S. H. Do , P. Lemmens , D. Wulferding , C. S. Woo , J. H. Lee , K. Chu , C. -H. Yang

We present a systematic study of the Raman spectra of optical phonons in graphene monolayers under tunable uniaxial tensile stress. Both the G and 2D bands exhibit significant red shifts. The G band splits into two distinct sub-bands (G+,…

Materials Science · Physics 2008-12-15 Mingyuan Huang , Hugen Yan , Changyao Chen , Daohua Song , Tony F. Heinz , James Hone

We combine polarization-resolved low frequency Raman microscopy and dispersion-corrected density-functional calculations (DFT-D3) to study polymorph-dependent lattice vibrations in coronene, a model molecular system for nanographenes and…

We report complex dielectric and Raman spectroscopy measurements in four samples of $\alpha$- Fe$_2$O$_3$, consisting of crystallites which are either hexagonal shaped plates or cuboids. All four samples exhibit the spin reorientation…

Strongly Correlated Electrons · Physics 2019-04-17 Namrata Pattanayak , Jitender Kumar , Partha Pratim Patra , G. V. Pavan Kumar , Ashna Bajpai

An intrinsic antiferromagnetic topological insulator $\mathrm{MnBi_2Te_4}$ can be realized by intercalating Mn-Te bilayer chain in a topological insulator, $\mathrm{Bi_2Te_3}$. $\mathrm{MnBi_2Te_4}$ provides not only a stable platform to…

We report on the phonon dynamics of LiYF4 obtained by direct method using first principle calculations. The agreement between experimental and calculated modes is satisfactory. An inversion between two Raman active modes is noticed compared…

Materials Science · Physics 2009-11-11 Benoit Minisini , Qiuping A. Wang , François Tsobnang

Phonons are quanta of lattice vibrations, and their modes (linear, circular, or stationary) are symmetry-determined. Circularly polarized phonons, possessing nonzero angular momentum (AM), have drawn widespread attention recently. Despite…

Materials Science · Physics 2026-01-09 Shuai Zhang , Zhiheng Huang , Muchen Du , Tianping Ying , Luojun Du , Tiantian Zhang

Here we have investigated the role of electron-phonon coupling on the Raman spectrum of narrow bandgap semiconductors APd3O4 (A = Ca, Sr) and hole-doped system Sr0.85Li0.15Pd3O4. Four Raman active phonons are observed at room temperature…

Strongly Correlated Electrons · Physics 2021-10-28 Bommareddy Poojitha , B. H. Reddy , Aprajita Joshi , Ankit Kumar , Asif Ali , R. S. Singh , Surajit Saha

Pressure-dependent Raman scattering studies in the range 0.0 -- 32 kbar were carried out in L-alanine in order to investigate its external mode phonon spectra in relation to the phase transitions in the crystal. A careful analysis of the…

Polarized infrared reflectivity spectra of a (110)-oriented TbScO3 single crystal plate were measured down to 10 K. The number of observed polar phonons active along the crystallographic c axis at low temperatures is much higher than…

The temperature and magnetic field dependence of lattice and carrier excitations in MnSi is studied in detail using inelastic light scattering. The pure symmetry components of the electronic response are derived from the polarization…

Strongly Correlated Electrons · Physics 2014-07-23 H. -M. Eiter , P. Jaschke , R. Hackl , A. Bauer , M. Gangl , C. Pfleiderer