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We present results of reflectivity measurements with E parallel to c and E perpendicular to c on NdBa2Cu3Ox (Nd123) single crystals close to full oxygen doping. Along the c-axis the optical conductivity shows a well developed absorption…

Superconductivity · Physics 2007-05-23 R. Hauff , M. Goeppert , B. Obst , Th. Wolf , P. Schweiss , H. Wuehl

We report femtosecond time-resolved reflectivity measurements of coherent phonons in tellurium performed over a wide range of temperatures (3K to 296K) and pump laser intensities. A totally symmetric A$_{1}$ coherent phonon at 3.6 THz…

Materials Science · Physics 2015-05-20 N. Kamaraju , Sunil Kumar , M. Anija , A. K. Sood

Reflectivity as a function of temperature for the La$_{0.67}$Ca$_{0.33}$MnO$_{3}$ (LCMO) film has been measured across the metal-insulator phase transition. The optical properties and their temperature dependence were determined in the…

Strongly Correlated Electrons · Physics 2018-04-02 Naween Anand , Naveen Margankunte , Hyoungjeen Jeen , A. F. Hebard , Amlan Biswas , David B. Tanner

We have investigated the charge dynamics and the nature of many-body interactions in La- and Pr- doped CaFe2As2. From the infrared part of the optical conductivity, we discover that the scattering rate of mobile carriers above 200 K…

The in-plane complex optical properties of the iron-chalcogenide superconductor FeTe0.55Se0.45 have been determined above and below the critical temperature Tc = 14 K. At room temperature the conductivity is described by a…

Superconductivity · Physics 2015-03-13 C. C. Homes , A. Akrap , J. S. Wen , Z. J. Xu , Z. W. Lin , Q. Li , G. D. Gu

The optical spectrum of the cubic helimagnetic metal FeGe has been investigated in the frequency range from 0.01 - 3.1 eV for different temperatures from 30 K to 296 K. The optical conductivity shows the evolution of a low energy (0.22 eV)…

Strongly Correlated Electrons · Physics 2013-01-24 V. Guritanu , D. van der Marel , J. Teyssier , T. Jarlborg , H. Wilhelm , M. Schmidt , F. Steglich

Superconductivity occurs in electrochemically doped molybdenum dichalcogenides samples thicker than four layers. While the critical temperature (Tc) strongly depends on the field effect geometry (single or double gate) and on the sample…

Superconductivity · Physics 2022-11-28 Giovanni Marini , Matteo Calandra

The a-axis optical properties of a detwinned single crystal of YBa_2Cu_3O_6.50 in the ortho II phase (Ortho II Y123, T_c= 59 K) were determined from reflectance data over a wide frequency range (70 - 42 000 cm^-1) for nine temperature…

Superconductivity · Physics 2009-11-11 J. Hwang , J. Yang , T. Timusk , S. G. Sharapov , J. P. Carbotte , D. A. Bonn , Ruixing Liang , W. N. Hardy

We measured the temperature dependence of the in-plane polarized reflectivity spectra of twin-free Y$_{1-x}$Ca$_{x}$Ba$_{2}$Cu$_{3}$O$_{7-{\delta}}$ single crystals with different Ca-concentrations (x=0,0.11 and 0.16) from optimally doped…

Superconductivity · Physics 2015-06-03 E. Uykur , K. Tanaka , T. Masui , S. Miyasaka , S. Tajima

The optical properties of thin films of the heavy-fermion compound CeCoIn5, which were deposited by molecular beam epitaxy onto MgF2 substrates, have been studied at frequencies 7 to 45 cm^{-1} (corresponding to 0.2 to 1.3 THz) and…

We report on a photo-induced transient state of YBa2Cu2O6+x in which transport perpendicular to the Cu-O planes becomes highly coherent. This effect is achieved by excitation with mid-infrared optical pulses, tuned to the resonant frequency…

Superconductivity · Physics 2014-06-04 S. Kaiser , C. R. Hunt , D. Nicoletti , W. Hu , I. Gierz , H. Y. Liu , M. Le Tacon , T. Loew , D. Haug , B. Keimer , A. Cavalleri

The effect of the electron temperature on both the light absorption and the scattering by metal nanoparticles (MNs) with excitation of the surface plasmon electron vibrations is studied in the framework of the kinetic theory. The formulae…

Mesoscale and Nanoscale Physics · Physics 2013-11-25 N. I. Grigorchuk

We present the anisotropic optical conductivity of MgB$_{2}$ between 0.1 and 3.7 eV at room temperature obtained on single crystals of different purity by the spectroscopic ellipsometry and reflectance measurements. The bare (unscreened)…

Superconductivity · Physics 2013-01-24 V. Guritanu , A. B. Kuzmenko , D. van der Marel , S. M. Kazakov , N. D. Zhigadlo , J. Karpinski

The resistivity of ultra-clean suspended graphene is strongly temperature dependent for 5K<T<240K. At T~5K transport is near-ballistic in a device of ~2um dimension and a mobility ~170,000 cm^2/Vs. At large carrier density, n>0.5*10^11…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 K. I. Bolotin , K. J. Sikes , J. Hone , H. L. Stormer , P. Kim

Ferroelectricity in atomically thin bilayer structures has been recently predicted1 and measured[2-4] in two-dimensional (2D) materials with hexagonal non-centrosymmetric unit-cells. Interestingly, the crystal symmetry translates lateral…

Europium Oxide (EuO), a low carrier density local moment ferromagnet, shows a wide variety of transport behaviour depending on preparative conditions. Some samples have a moderate resistivity with a modest peak near $T_c$ while others show…

Strongly Correlated Electrons · Physics 2025-06-18 Tanmoy Mondal , Pinaki Majumdar

When an excess charge carrier is added to a one-dimensional (1D) semiconductor immersed in a polar solvent, the carrier can undergo self-localization into a large-radius adiabatic polaron. We explore the local optical absorption from the…

Materials Science · Physics 2009-11-13 G. L. Ussery , Yu. N. Gartstein

Optical properties of nanocrystalline red-emitting phosphor, Europium doped Yttria (Y$_{2}$O$_{3}$:Eu$^{3+})$, of average particle size 15 nm are investigated. The intensity of the strongest emission line at 612 nm is found to be highest in…

Materials Science · Physics 2009-11-10 S. Ray , A. Singha , P. Pramanik , Anushree Roy

The collective oscillations of surface charges (surface plasmons) induced by light-matter interactions were predicted in the 1950s to influence electrical conduction in 2D noble metals. Primarily two mechanisms were predicted and later by…

Mesoscale and Nanoscale Physics · Physics 2020-06-19 Suresh C Sharma , Vivek Khichar , Hussein Akafzade , Nader Hozhabri

We theoretically consider the temperature and density dependent transport properties of semiconductor-based 2D carrier systems within the RPA-Boltzmann transport theory, taking into account realistic screened charged impurity scattering in…

Strongly Correlated Electrons · Physics 2009-11-10 S. Das Sarma , E. H. Hwang