Pseudogapped Fermi surfaces of1T−TaS2and1T−TaSe2:A charge density wave effect

The structural instabilities towards the formation of a charge density wave (CDW) ground state exhibited by several layered Mo and W bronzes and oxides are reviewed. It is shown that in these two-dimensional (2D) metals, including the purple bronzes A x Mo 6 O 17 (A=K, Na, Tl; x≈1), the γ and η phases of MO 4 O 11 and the monophosphate tungsten bronzes with pentagonal tunnels ( PO 2)4 ( WO 3)2m(m=4, 6, 7), the CDW instability can be associated with particular chains of MoO 6 or WO 6 octahedra of the ReO 3 type slabs along which there is a strong overlap of the t 2g orbitals. The CDW critical wave vectors of the purple bronzes, Mo 4 O 11 and the tungsten bronzes with m=4 and 6 lead to a common nesting between differently oriented 1D Fermi surfaces. It is suggested that the anharmonic CDW modulation, which occurs in the tungsten bronzes with m≥7, could be the structural fingerprint of electron localization effects.

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Quasi-one-dimensional superconductivity in the pressurized charge-density-wave conductor HfTe3

npj Quantum Materials ◽

10.1038/s41535-021-00393-8 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Z. Y. Liu ◽

J. Li ◽

J. F. Zhang ◽

J. Li ◽

P. T. Yang ◽

...

Keyword(s):

Charge Density ◽

Charge Density Wave ◽

Ambient Pressure ◽

Density Wave ◽

Fermi Surfaces ◽

One Dimensional ◽

Transmission Electron ◽

Pressure Transport ◽

A Charge ◽

Superconducting Pairing

AbstractHfTe3 single crystal undergoes a charge-density-wave (CDW) transition at TCDW = 93 K without the appearance of superconductivity (SC) down to 50 mK at ambient pressure. Here, we determined its CDW vector q = 0.91(1) a* + 0.27(1) c* via low-temperature transmission electron microscope and then performed comprehensive high-pressure transport measurements along three major crystallographic axes. Our results indicate that the superconducting pairing starts to occur within the quasi-one-dimensional (Q1D) -Te2-Te3- chain at 4–5 K but the phase coherence between the superconducting chains cannot be realized along either the b- or c-axis down to at least 1.4 K, giving rise to an extremely anisotropic SC rarely seen in real materials. We have discussed the prominent Q1D SC in pressurized HfTe3 in terms of the anisotropic Fermi surfaces arising from the unidirectional Te-5px electronic states and the local pairs formed along the -Te2-Te3- chains based on the first-principles electronic structure calculations.

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Holographic Fermi surfaces in charge density wave from D2-D8

Journal of High Energy Physics ◽

10.1007/jhep09(2021)160 ◽

2021 ◽

Vol 2021 (9) ◽

Author(s):

Subir Mukhopadhyay ◽

Nishal Rai

Keyword(s):

Dirac Equation ◽

Fermi Surface ◽

Spectral Density ◽

Charge Density ◽

Charge Density Wave ◽

Density Wave ◽

Spin Density Wave ◽

Fermi Surfaces ◽

A Charge ◽

Ionic Lattice

Abstract D2-D8 model admits a numerical solution that corresponds to a charge density wave and a spin density wave. Considering that as the background, we numerically solve the Dirac equation for probe fermions. From the solution, we obtain the Green’s function and study the behaviour of the spectral density. We begin with generic fermions and have studied the formation of the Fermi surface and where it develops a gap. In addition, we have incorporated an ionic lattice and study its effect on the Fermi surface. Then we analysed the worldvolume fermions. In this particular model we do not find Fermi surface for the dual operators.

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Ultrafast formation of domain walls of a charge density wave in SmTe3

Physical Review B ◽

10.1103/physrevb.103.054109 ◽

2021 ◽

Vol 103 (5) ◽

Author(s):

M. Trigo ◽

P. Giraldo-Gallo ◽

J. N. Clark ◽

M. E. Kozina ◽

T. Henighan ◽

...

Keyword(s):

Charge Density ◽

Charge Density Wave ◽

Domain Walls ◽

Density Wave ◽

A Charge

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Ultrafast switching to an insulating-like metastable state by amplitudon excitation of a charge density wave

Nature Physics ◽

10.1038/s41567-021-01267-3 ◽

2021 ◽

Author(s):

Naotaka Yoshikawa ◽

Hiroki Suganuma ◽

Hideki Matsuoka ◽

Yuki Tanaka ◽

Pierre Hemme ◽

...

Keyword(s):

Charge Density ◽

Metastable State ◽

Charge Density Wave ◽

Density Wave ◽

Ultrafast Switching ◽

A Charge

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Ultrafast spot-profile LEED of a charge-density wave phase transition

Applied Physics Letters ◽

10.1063/5.0052603 ◽

2021 ◽

Vol 118 (22) ◽

pp. 221603

Author(s):

G. Storeck ◽

K. Rossnagel ◽

C. Ropers

Keyword(s):

Phase Transition ◽

Charge Density ◽

Charge Density Wave ◽

Density Wave ◽

Wave Phase ◽

Charge Density Wave Phase ◽

A Charge

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A study of the magnetoresistance of the charge-transfer salt at hydrostatic pressures of up to 20 kbar: evidence for a charge-density-wave ground state and the observation of pressure-induced superconductivity

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/8/33/009 ◽

1996 ◽

Vol 8 (33) ◽

pp. 6005-6017 ◽

Cited By ~ 25

Author(s):

W Lubczynski ◽

S V Demishev ◽

J Singleton ◽

J M Caulfield ◽

L du Croo de Jongh ◽

...

Keyword(s):

Charge Transfer ◽

Charge Density ◽

Ground State ◽

Charge Density Wave ◽

Density Wave ◽

A Charge

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An experimentalist's view of the galvanomagnetic and thermomagnetic properties of potassium

Canadian Journal of Physics ◽

10.1139/p82-095 ◽

1982 ◽

Vol 60 (5) ◽

pp. 679-686 ◽

Cited By ~ 12

Author(s):

R. Fletcher

Keyword(s):

Experimental Investigation ◽

Charge Density ◽

Charge Density Wave ◽

High Field ◽

Density Wave ◽

The Other ◽

Detailed Structure ◽

Precise Nature ◽

A Charge ◽

Thermomagnetic Properties

This paper provides a brief survey of the experimental and theoretical situation regarding the galvano- and thermomagnetic properties of potassium viewed within the context of the behaviour of other metals. Most of the data are consistent with various sample imperfections as being the major source of the anomalies that are found. However, the precise nature of the imperfections and the mechanism by which the imperfections produce the anomalies are not yet known. It is argued that the recently discovered detailed structure in the high field induced torque of K should be subjected to intensive experimental investigation before drawing any conclusions with regards to the possible presence of a charge density wave; the other magnetotransport properties offer little evidence either for or against such a possibility.

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