scholarly journals Optical properties of the Ce and La ditelluride charge density wave compounds

2007 ◽  
Vol 75 (20) ◽  
Author(s):  
M. Lavagnini ◽  
A. Sacchetti ◽  
L. Degiorgi ◽  
K. Y. Shin ◽  
I. R. Fisher
Keyword(s):  
Optical Properties ◽  
Charge Density ◽  
Charge Density Wave ◽  
Density Wave

Optical properties of the charge-density-wave compoundCeTe2

2008 ◽  
Vol 78 (13) ◽  
Author(s):  
K. E. Lee ◽  
C. I. Lee ◽  
H. J. Oh ◽  
M. A. Jung ◽  
B. H. Min ◽  
...  
Keyword(s):  
Optical Properties ◽  
Charge Density ◽  
Charge Density Wave ◽  
Density Wave

scholarly journals Pressure dependence of the optical properties of the charge-density-wave compoundLaTe2

2008 ◽  
Vol 77 (16) ◽  
Author(s):  
M. Lavagnini ◽  
A. Sacchetti ◽  
L. Degiorgi ◽  
E. Arcangeletti ◽  
L. Baldassarre ◽  
...  
Keyword(s):  
Optical Properties ◽  
Charge Density ◽  
Pressure Dependence ◽  
Charge Density Wave ◽  
Density Wave

Layered tungsten bronzes: Tuning the optical properties by changing the layer thickness

2002 ◽  
Vol 12 (9) ◽  
pp. 361-361
Author(s):  
J. L. Musfeldt ◽  
Z. T. Zhu ◽  
Z. S. Teweldemedhin ◽  
M. Greenblatt
Keyword(s):  
Optical Properties ◽  
Charge Density ◽  
Layer Thickness ◽  
Charge Density Wave ◽  
Variable Temperature ◽  
Density Wave ◽  
Low Frequency ◽  
Gap Formation ◽  
Octahedral Layer ◽  
Charge Localization

We investigated the optical properties of a series of monophosphate tungsten bronzes (P02)4(W03)2m (m=2,4, 6,7) as a function of layer thickness, with special attention on the m=7 density wave superconductor. These materials have several layers of corner-sharing WO6 octahedra separated by one PO4 layer, leading to a tunable octahedral layer thickness with m. In the optical regime, the spectra of the m=2, 4, 6, and 7 materials display an anisotropic electronic excitation, originating from the W intra t2g d to d transition. The intensities and frequencies of these excitations vary with the octahedral layer thickness, consistent with a softer lattice with increasing m. The low-frequency electrodynamics of the monophosphate tungsten bonzes show a gap or pseudogap feature in the infrared, demonstrating a ubiquitous bound camer response. The m=7 density wave superconductor is especially interesting. The variable temperature ab-plane spectra display a suppression of the optical conductivity along the b-axis below 140 K, giving rise to charge localization and anisotropic charge density wave gap formation near 1400 cm-1. This middle infrared charge localization is directly related to the appearance of both flat and dispersive bands along b. Although oscillator strength is redistributed among the free carrier response, charge density wave gap absorption, and d to d transition in the density wave states, the spectral weight is largely conserved below the plasma frequency. Based upon these observations, P4W 14050 is another example of a superconductor with an unusual normal state.

Optical properties of the charge-density-wave rare-earth tri-telluride compounds: A view on

2009 ◽  
Vol 404 (3-4) ◽  
pp. 533-536 ◽  
Author(s):  
F. Pfuner ◽  
L. Degiorgi ◽  
J.-H. Chu ◽  
N. Ru ◽  
K.Y. Shin ◽  
...  
Keyword(s):  
Optical Properties ◽  
Rare Earth ◽  
Charge Density ◽  
Charge Density Wave ◽  
Density Wave

Incommensurate modulated phases of the NbxTa1-xTe4 charge density wave system

1992 ◽  
Vol 50 (1) ◽  
pp. 58-59
Author(s):  
S. Ritchie ◽  
J. C. Bennett ◽  
A. Prodan ◽  
F.W. Boswell ◽  
J.M. Corbett
Keyword(s):  
Charge Density ◽  
Charge Density Wave ◽  
Direct Evidence ◽  
Density Wave ◽  
Wave System ◽  
Modulated Phases ◽  
Metal Atoms ◽  
Incommensurate Modulation ◽  
End Members ◽  
Modulation Wave Vector

A continuous sequence of compounds having composition NbxTa1-xTe4; 0 ≤ x ≤ 1 have been studied by electron diffraction and microscopy. Previous studies have shown that the end members of the series, TaTε4 and NbTε4 possess a quasi-one-dimensional character and exhibit charge density wave (CDW) distortions. In these compounds, the subcell structure is tetragonal with axes (a × a × c) and consists of the metal atoms (Nb or Ta) centered within an extended antiprismatic cage of Te atoms. At room temperature, TaTε4 has a commensurate modulation structure with a 2a × 2a × 3c unit cell. In NbTε4, an incommensurate modulation with × ∼ 16c axes is observed. Preliminary studies of the mixed compounds NbxTα1-xTε4 showed a discontinuous jump of the modulation wave vector commensurate to incommensurate when the Nb dopant concentration x, exceeded x ≃ 0.3, In this paper, the nature of the compositional dependence of is studied in greater detail and evidence is presented for a stepwise variation of . This constitutes the first direct evidence for a Devil's staircase in CDW materials.

Wave Analysis of the Charge Density Wave Dynamics in the Molecular Conductor (Perylene)2Pt(mnt)2 (mnt=maleonitriledithiolate)

1995 ◽  
Vol 5 (5) ◽  
pp. 539-545 ◽  
Author(s):  
J. Dumas ◽  
N. Thirion ◽  
M. Almeida ◽  
E. B. Lopes ◽  
M. J. Matos ◽  
...  
Keyword(s):  
Charge Density ◽  
Charge Density Wave ◽  
Density Wave ◽  
Wave Analysis ◽  
Wave Dynamics ◽  
Molecular Conductor
Sign in / Sign up

Export Citation Format

Share Document