Possibility of a metallic phase in the charge-density-wave–spin-density-wave crossover region in the one-dimensional Hubbard-Holstein model at half filling

By using the bosonization approach and the renormalization group (RG) technique, we study the half-filled band one-dimensional t–U–J model with additional on-bond repulsion (W>0) in the weak-coupling regime. The presence of on-bond repulsion is responsible for realization of a metallic phase in the system, and the phase diagram is strongly controlled by the symmetry of the model. By analyzing the RG flow diagram and comparing order parameters, the phase boundaries are determined and the structure of the phase diagram is clarified. In the case of SU (2) ⊗ SU (2) symmetry, the phase diagram consists of a metallic phase characterized by a Luttinger liquid (LL) and two insulting phases characterized by the degenerate spin-density-wave (SDW) and the bond-charge-density-wave (BCDW). In the SU (2) ⊗ U(1)-symmetric case, the phase diagram contains two metallic phases: a LL and a Luther–Emery phase, and three insulating phases: the transverse SDW ( SDW ±), the longitudinal SDW ( SDW z) and the dimerized BCDW. The insulating charge-density-wave and bond-spin-density-wave (BSDW) phases are always suppressed in the ground state. In addition, the system show a long-ranged order in the BCDW and SDW z phases.

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Existence of an Intermediate Metallic Phase at the SDW-CDW Crossover Region in the One-Dimensional Holstein-Hubbard Model at Half-Filling

Advances in Condensed Matter Physics ◽

10.1155/2010/350787 ◽

2010 ◽

Vol 2010 ◽

pp. 1-14 ◽

Cited By ~ 7

Author(s):

Ashok Chatterjee

Keyword(s):

Hubbard Model ◽

High Temperature Superconductivity ◽

Density Wave ◽

Spin Density Wave ◽

Coulomb Repulsion ◽

Metallic Phase ◽

Variational Calculation ◽

Crossover Region ◽

One Dimensional ◽

Half Filling

The Holstein-Hubbard model serves as a useful framework to investigate this interplay between the phonon-induced electron-electron attractive interaction and the direct Coulomb repulsion and can afford interesting phase diagrams due to competition among charge-density wave (CDW), spin-density wave (SDW), and superconductivity. However the detailed nature of the CDW-SDW transition is still not very well known. It is generally believed that the system undergoes a direct insulator to insulator transition from CDW to SDW with the increase of the on-site Coulomb repulsion for a given strength of the electron-phonon coupling and this is the main bottleneck for the polaronic/bipolaronic mechanism of high-temperature superconductivity. We have recently made an investigation to study the nature of the transition from SDW phase to CDW phase within the framework of a one-dimensional Holstein-Hubbard model at half-filling using a variational method. We find that an intervening metallic phase may exist at the crossover region of the CDW-SDW transition. We have also observed that if the anharmonicity of the phonons is taken into account, this metallic phase widens and the polarons become more mobile, which is a more favorable situation from the point of view of superconductivity. We shall finally show that an improved variational calculation widens the metallic phase and makes the polarons more mobile, which reconfirms the existence of the intermediate metallic phase at the SDW-CDW crossover region.

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Luttinger liquid versus charge density wave behaviour in the one-dimensional spinless fermion Holstein model

Physica B Condensed Matter ◽

10.1016/j.physb.2005.01.198 ◽

2005 ◽

Vol 359-361 ◽

pp. 699-701 ◽

Cited By ~ 10

Author(s):

H. Fehske ◽

G. Wellein ◽

G. Hager ◽

A. Weiße ◽

K.W. Becker ◽

...

Keyword(s):

Charge Density ◽

Charge Density Wave ◽

Density Wave ◽

Luttinger Liquid ◽

One Dimensional ◽

Spinless Fermion ◽

Holstein Model ◽

The One

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Quantum coherence and decoherence of correlated electron states in the one-dimensional charge-density-wave–spin-density-wave phase transition

Physical Review B ◽

10.1103/physrevb.73.115105 ◽

2006 ◽

Vol 73 (11) ◽

Cited By ~ 3

Author(s):

Norikazu Tomita

Keyword(s):

Phase Transition ◽

Charge Density ◽

Spin Density ◽

Charge Density Wave ◽

Quantum Coherence ◽

Density Wave ◽

Spin Density Wave ◽

One Dimensional ◽

Correlated Electron ◽

The One

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Deformation of sliding charge density wave in Rb0.3MoO3

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20020428 ◽

2002 ◽

Vol 12 (9) ◽

pp. 323-324

Author(s):

D. Le Bolloc'h ◽

S. Ravy ◽

P. Senzier ◽

C. Pasquier ◽

C. Detlefs

Keyword(s):

Charge Density ◽

Correlation Length ◽

Charge Density Wave ◽

Density Wave ◽

Relaxation Times ◽

X Ray Diffraction ◽

Electrical Field ◽

One Dimensional ◽

High Q ◽

The One

The correlation length of the charge density wave ordering in Rb0.3, MoO, has been studied by x-ray diffraction under electric field applied along the one-dimensional axis. The (10, 0.25, -5.5) satellite reflection has been measured in 3D, using high Q-resolution available at the ESRF. Under electrical field, the satellite reaches two stable positions depending on the temperature. It can switch from one to another as a function of the temperature and the current with very long relaxation times ($\rm 10^{th}$ of minutes). After several cycling with T and E, the satellite reflection is found to shift in the 3 main directions. The width of the satellite is reduced by a factor of two in the k-direction and an increase of the transverse correlation length is observed in the two others: the ordered domains look elongated, reaching until 5000 Å in the direction of the applied field and around 1OOO Å, in the perpendicular directions.

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