Related papers: Nernst effect, quasiparticles, and d-density waves…
We investigate the transport properties of La$_{1.8-x}$Eu$_{0.2}$Sr$_x$CuO$_4$ ($x=0.04$, 0.08, 0.125, 0.15, 0.2) with a special focus on the Nernst effect in the normal state. Various anomalous features are present in the data. For…
Unconventional density wave (UDW) has been speculated as a possible electronic ground state in excitonic insulator in 1968. Recent surge of interest in UDW is partly due to the proposal that the pseudogap phase in high T_c cuprate…
The Nernst effect has recently proven as a sensitive probe for detecting unusual normal state properties of unconventional superconductors. Here we present a systematic study of the Nernst effect of the iron pnictide superconductor \laf…
One of the puzzling characteristics of the pseudogap phase of high-$T_c$ cuprates is the nodal-antinodal dichotomy. While the nodal quasiparticles have a Fermi liquid behaviour, the antinodal ones show non-Fermi liquid features and an…
We study the behavior of the Hall coefficient, $R_H$, in a system exhibiting $d_{{x^2}-{y^2}}$ density-wave (DDW) order in a regime in which the carrier concentration, $x$, is tuned to approach a quantum critical point at which the order is…
Angle-resolved photoemission spectra present two challenges for the d-density wave (DDW) theory of the pseudogap state of the cuprates: (1) hole pockets near $(\pi/2,\pi/2)$ are not observed, in apparent contradiction with the assumption of…
Charge density-wave order has been observed in cuprate superconductors whose crystal structure breaks the square symmetry of the CuO2 planes, such as orthorhombic YBa2Cu3Oy (YBCO), but not so far in cuprates that preserve that symmetry,…
Pair density wave (PDW) is a distinct superconducting state characterized by a periodic modulation of its order parameter in real space. Its intricate interplay with the charge density wave (CDW) state is a continuing topic of interest in…
We analyze fermionic spectral function in the spin-density-wave (SDW) phase of quasi-2D cuprates at small but finite T. We use a non-perturbative approach and sum up infinite series of thermal self-energy terms, keeping at each order…
We consider various incommensurate (IC) order parameters for electrons on a square lattice which reduce to $d_{x^2-y^2}$-density wave (DDW) order when the ordering wavevector ${\bf Q}\to (\pi,\pi)$. We describe the associated charge and…
We present a valence transition model for electron- and hole-doped cuprates, within which there occurs a discrete jump in ionicity Cu$^{2+} \to$ Cu$^{1+}$ upon doping, at or near optimal doping in the electron-doped compounds and at the…
Superconducting mechanism of cuprates is discussed in the light of the proximity of the Mott insulator. The proximity accompanied by suppression of coherence takes place in an inhomogeneous way in the momentum space in finite-dimensional…
We show that the d-wave ordering in particle-hole channels, dubbed d-wave checkerboard order, possesses important physics that can sufficiently explain the scanning tunneling microscopy (STM) results in cuprates. A weak d-wave checkerboard…
One of the most puzzling facts about cuprate high-temperature superconductors in the lightly doped regime is the coexistence of uniform superconductivity and/or antiferromagnetism with many low-energy charge-ordered states in a…
We examine the possibility that the experimentally observed enhancement of superconducting (SC) fluctuations above the SC transition temperature in the underdoped cuprates is caused by stripes -- an intrinsic electronic inhomogeneity,…
We consider the effects of a perpendicular magnetic field on the d-density wave order and conclude that if the pseudogap phase in the cuprates is due to this order, then it is highly insensitive to the magnetic field in the underdoped…
The pseudogap phase of high-$T_c$ cuprates is controversially attributed to preformed pairs or to a phase which coexists and competes with superconductivity. One of the challenges is to develop theoretical and experimental studies in order…
The presence of incommensurate spiral spin-density waves (SDW) has been proposed to explain the $p$ (hole doping) to $1+p$ jump measured in the Hall number $n_H$ at a doping $p^*$. Here we explore {\it collinear} incommensurate SDW as…
We examine trends in the wavevectors and form-factors of charge density wave instabilities of three-band models of the underdoped cuprates. For instabilities from a high temperature state with a large Fermi surface, we extend a study by…
When a superconductor is warmed above its critical temperature $T_c$, long range order is destroyed by fluctuations in the order parameter. These fluctuations can be probed by measurements of conductivity, diamagnetism, and of the Nernst…