相关论文: Raman study of Twin Free YBa$_2$Cu$_3$O$_{6.5}$ (O…
The Ortho-II phase of YBa$_2$Cu$_3$O$_6.5$ is characterized by a periodic alternation of empty Cu and filled Cu-O b-axis doubling the unit cell in the a direction. The extra oxygen in the full chains gives rise to an attractive potential…
The novel ferroelectric-like structural transition observed in metallic LiOsO$_3$ [Y. Shi et al., Nat. Mater. 12, 1024 (2013)], has invoked many theoretical and experimental interests. In this work, we have performed polarized and…
Electronic Raman scattering experiments in a wide variety of materials (ranging from mixed-valence materials to Kondo insulators to high-temperature superconductors) show anomalous behavior in the B_{1g} channel when the system is on the…
We have performed Raman-scattering measurements on high-quality single crystals of A$_{0.8}$Fe$_{1.6}$Se$_2$ superconductors of several compositions. We find a broad, asymmetric peak around 1600 cm$^{-1}$ (200 meV), which we identify as a…
We have performed polarized electronic Raman scattering on URu2Si2 single crystals at low temperature down to 8 K in the hidden order state and under magnetic field up to 10 T. The hidden order state is characterized by a sharp excitation…
We report a comparative Raman spectroscopic study of the quasi-one-dimensional charge-density-wave systems \ab (A = K, Rb). The temperature and polarization dependent experiments reveal charge-coupled vibrational Raman features. The…
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…
Lead sulfide is an important semiconductor that has found technological applications for over a century. Raman spectroscopy, a standard tool for the investigation and characterization of semiconductors, has limited application to this…
We have performed for the first time micro-Raman studies of lysozyme crystals for the temperatures lower than the room one (in the range 282-300K). Anomalous temperature dependence of the positions of Raman scattering bands has been…
Raman scattering (RS) in bulk hafnium disulfide (HfS$_2$) is investigated as a function of temperature (5 K $-$ 350 K) with polarization resolution and excitation of several laser energies. An unexpected temperature dependence of the…
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…
(Sr$_{2}$,Ba$_{2}$)Cu$_{3}$O$_{4}$Cl$_{2}$ are antiferromagnetic insulators which are akin to the parent compounds of the cuprate superconductors but with two distinct magnetic ordering temperatures related to two magnetic Cu$_{I}$ and…
Two aspects in connection with the magnetic properties of La_{2-x-y}Nd_ySr_xCuO_4 single crystals are discussed. The first is related to long wavelength magnetic excitations in x = 0, 0.01, and 0.03 La_{2-x}Sr_xCuO_4 detwinned crystals as a…
We use inelastic light scattering to study Sr$_{1-x}$Na$_x$Fe$_2$As$_2$ ($x\approx0.34$), which exhibits a robust tetragonal magnetic phase that restores the four-fold rotation symmetry inside the orthorhombic magnetic phase. With cooling,…
The lattice dynamics of Ba$_2$CuGe$_2$O$_7$, a compound which develops Dzyaloshinsky-Moriya (DM) helical magnetism below $T_N$ = 3.2 K, has been studied by measuring the infrared reflectivity of a single crystal with the radiation polarized…
The Raman spectrum of Ba2CuGe2O7, a tetragonal insulator which develops Dzyaloshinsky- Moriya helical magnetism below TN = 3.2 K, has been detected at temperatures varying from 300 to 80 K in a single crystal, with the radiation polarized…
Time resolved measurements provide a new way to disentangle complex interactions in quantum materials due to their different timescales. We used pump-probe Raman scattering to investigate the apical oxygen vibration in…
We present low temperature Raman measurements on Ca3Co2O6. Shell model lattice dynamics calculations were done to determine the vibrational pattern of the expected Raman modes. In the temperature window 300K to 52K the mode frequencies and…
The pressure-induced changes in the optical properties of $\beta$-Na$_{0.33}$V$_2$O$_5$ single crystals at room temperature were studied by polarization-dependent Raman and far-infrared reflectivity measurements under high pressure. From…
The isospin-phonon coupling in Sr2IrO4 is investigated by temperature dependent phonon Raman scattering. Anomalous behavior in the frequency of all studied optical phonons is observed below the magnetic transition temperature TN ~240 K. The…