Phase transitions to dipolar clusters and charge density waves in high Tc superconductors

Abstract

We show that doping of hole charge carriers leads to formation of electric dipolar clusters in cuprates. They are created by many-body interactions between the dopant ion outside and holes inside the CuO planes. Because of the two-fold degeneracy holes in the CuO plane cluster into four-particles resonance valence bond plaquettes bound with dopant ions. Such dipoles may order into charge-density waves (CDW) or stripes or form a disordered state depending on doping and temperature. The lowest energy of the ordered system corresponds to a local anti-ferroelectric ordering. The mobility of individual disordered dipoles is very low at low temperatures and they prefer first to bind into dipole-dipole pairs. Electromagnetic radiation interacts strongly with electric dipoles and when the sample is subjected to it the mobility changes significantly. This leads to a fractal growth of dipolar clusters. The existence of electric dipoles and CDW induce two phase transitions with increasing temperature, melting of the ordered state and disappearance of the dipolar state. Ferroelectricity at low doping is a natural consequence of such dipole moments. We develop a theory based on two-level systems and dipole-dipole interaction to explain the behavior of the polarization as a function of temperature and electric field.

11 pages 11 Figures

References in corpus (11)

• Energy gaps in high-transition temperature cuprate superconductors
• From a single-band metal to a high-temperature superconductor via two thermal phase transitions (Supporting Material)
• From a single-band metal to a high-temperature superconductor via two thermal phase transitions
• Scale-free structural organization of oxygen interstitials in La2CuO4+y
• Phase competition in trisected superconducting dome
• Optimum inhomogeneity of local lattice distortions in La2CuO4+y
• Point nodes persisting far beyond Tc in Bi2212
• Strong charge fluctuations manifested in the high-temperature Hall coefficient of high-T_c cuprates
• Femtosecond x rays link melting of charge-density wave correlations and light-enhanced coherent transport in YBa2Cu3O6.6
• Doping dependence of chemical potential and entropy in hole- and electron-doped high-Tc cuprates
• Unusual photoemission resonances of oxygen-dopant induced states in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+x}$

Cited by in corpus (2)

• Ionic liquid gating induced two superconductor-insulator phase transitions in spinel oxide Li${}_{1\pm x}$Ti${}_2$O${}_{4-\delta }$
• Dislocations as a boundary between charge density wave and oxygen rich phases in a cuprate high temperature superconductor