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相关论文: Lattice and electronic anomalies of CaFe_2As_2 stu…

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We report the polarized Raman spectra of undoped ReOFeAs (Re = Sm, La) collected at room temperature from $ab$ surfaces of impurity free microcrystals. The spectra exhibit sharp phonon lines on very weak electronic scattering background.…

超导电性 · 物理学 2008-04-16 V. G. Hadjiev , M. N. Iliev , K. Sasmal , Y. -Y. Sun , C. W. Chu

Spin and lattice dynamics of CaMn7O12 ceramics were investigated using infrared, THz and inelastic neutron scattering (INS) spectroscopies in the temperature range 2 to 590 K, and, at low temperatures, in applied magnetic fields of up to 12…

Zn(CN)2 is known to have an isotropic negative thermal expansion (NTE) coefficient (about -51 x 10-6 K-1) over 10-370 K that is twice as large as that of ZrW2O8. We have measured the pressure dependence of the phonon spectra up to 30 meV…

材料科学 · 物理学 2015-05-13 R. Mittal , S. L . Chaplot , H. Schober

Magneto Raman scattering study of the E$_{2g}$ optical phonons in multi-layer epitaxial graphene grown on a carbon face of SiC are presented. At 4.2K in magnetic field up to 33 T, we observe a series of well pronounced avoided crossings…

材料科学 · 物理学 2015-05-13 C. Faugeras , M. Amado , P. Kossacki , M. Orlita , M. Sprinkle , C. Berger , W. A. de Heer , M. Potemski

We report on Raman scattering experiments of the undoped SrFe2As2 and superconducting Sr0.85K0.15Fe2As2 (Tc=28K) and Ba0.72K0.28Fe2As2 (Tc=32K) single crystals. The frequency and linewidth of the B1g mode at 210 cm-1 exhibits an appreciable…

超导电性 · 物理学 2015-05-14 K. -Y. Choi , P. Lemmens , I. Eremin , G. Zwicknagl , H. Berger , G. L. Sun , D. L. Sun , C. T. Lin

Although the rutile structure of TiO$_2$ is stable at high temperatures, the conventional quasiharmonic approximation predicts that several acoustic phonons decrease anomalously to zero frequency with thermal expansion, incorrectly…

材料科学 · 物理学 2015-08-19 Tian Lan , C. W. Li , O. Hellman , D. Kim , J. A. Muñoz , H. Smith , D. L. Abernathy , B. Fultz

The study of phonon coupling in doped semiconductors via electrical transport measurements is challenging due to unwanted temperature-induced effects such as dopant ionisation and parallel conduction. Here, we study phonon scattering in 2D…

介观与纳米尺度物理 · 物理学 2025-03-03 Y. Ashlea Alava , K. Kumar , C. Harsas , P. Mehta , P. Hathi , C. Chen , D. A. Ritchie , A. R. Hamilton

We explore the Fano resonance in ZrTe5, using Raman scattering measurements. We identified two closely spaced B2g phonon modes, B2g I and B2g II, around 9 meV and 10 meV, respectively. Interestingly, only B2g I exhibited the Fano resonance,…

Polarized Raman-scattering spectra of superconducting, single-crystalline FeSe evidence pronounced phonon anomalies with temperature reduction. A large 6.5% hardening of the B_1g(Fe) phonon mode is attributed to the suppression of local…

We report detailed measurements of composition as well as temperature dependence of the phonon density-of-states in a new series of FeAs compounds with composition CaFe1\_{1-x}Co\_{x}AsF (x = 0, 0.06, 0.12). The composition as well as…

We report a polarized Raman study of Weyl semimetal TaAs. We observe all the optical phonons, with energies and symmetries consistent with our first-principles calculations. We detect additional excitations assigned to multiple-phonon…

材料科学 · 物理学 2015-08-12 H. W. Liu , P. Richard , Z. D. Song , L. X. Zhao , Z. Fang , G. -F. Chen , H. Ding

The temperature effect on the Raman scattering efficiency is investigated in $\varepsilon$-GaSe and $\gamma$-InSe crystals. We found that varying the temperature over a broad range from 5 K to 350 K permits to achieve both the resonant…

We present neutron inelastic scattering measurements of the low-energy phonons in single crystal BiFeO3. The dispersions of the three acoustic phonon modes (LA along [100], TA1 along [010] and TA2 along [110]) and two low energy optic…

We report on the dynamics of coherent phonons in semimetal 1T'-MoTe2 using femtosecond pump-probe spectroscopy. On an ultrafast sub-picosecond time scale at room temperature, a low frequency and long-lifetime shear phonon mode was observed…

材料科学 · 物理学 2020-03-09 T. Fukuda , K. Makino , Y. Saito , P. Fons , A. V. Kolobov , K. Ueno , M. Hase

We determine from first-principles the finite-temperature properties--linewidths, line shifts, and lifetimes--of the key vibrational modes that dominate inelastic losses in graphitic materials. In graphite, the phonon linewidth of the…

材料科学 · 物理学 2007-10-25 Nicola Bonini , Michele Lazzeri , Nicola Marzari , Francesco Mauri

We use Raman scattering to study spin, charge, and lattice dynamics in various phases of Ca_{2-x}Sr_{x}RuO_{4}. With increasing substitution of Ca by Sr in the range 0 =< x < 0.2, we observe (1) evidence for an increase of the…

强关联电子 · 物理学 2009-11-10 H. Rho , S. L. Cooper , S. Nakatsuji , H. Fukazawa , Y. Maeno

We have carried out temperature-dependent x-ray diffraction and Raman scattering experiments on powder $Cs_3Bi_2Br_9$. Trigonal to monoclinic structural transition at around 95 K is discussed and shown to be driven by the softening of the…

We have studied polarized Raman spectra of (TMTSF)2PF6 single crystals in the wide spectral and temperature range using different laser energies. We observed and assigned 23 Raman active modes. The carbon C=C in-phase and out-of-phase…

强关联电子 · 物理学 2007-05-23 Z. V. Popovic , V. A. Ivanov , O. P. Khoung , T. Nakamura , G. Saito , V. V. Moshchalkov

Electronic Raman scattering and optical phonon self-energies are studied on single crystals of $LuB_{12}$ with different isotopic composition in the temperature region 10-650K and at pressures up to 10 GPa. The shape and energy position of…

材料科学 · 物理学 2016-08-09 Yu. S. Ponosov , A. A. Makhnev , S. V. Streltsov , V. B. Filipov , N. Yu. Shitsevalova

Despite the tremendous progress in spintronic studies of van der Waals (vdW) room-temperature ferromagnet Fe3GaTe2, much less effort has been spent on its lattice dynamics and possible interaction with spintronic degrees of freedom. In this…

材料科学 · 物理学 2025-06-12 Xia Chen , Xi Zhang , Wenjie He , Yu Li , Jiating Lu , Dinghua Yang , Deren Li , Li Lei , Yong Peng , Gang Xiang