Spectral function method for Hall conductivity of incoherent metals

Using a model spectral function of the electron the Hall conductivity in the normal metallic state of the Pr_{2-x}Ce_xCuO_4 (PCCO) superconductor is calculated neglecting the current vertex-correction. The result is qualitatively consistent with the experiment. Consequently the reason becomes clear why the Fermi-liquid theory fails to explain the anomaly of the Hall conductivity. The inconsistency of the fluctuation-exchange approximation also becomes clear.Comment: arXiv admin note: substantial text overlap with arXiv:1204.530

Comment on Theory of Hall Effect and Electrical Transport in High-Tc Cuprates: Effects of Antiferromagnetic Spin Fluctuations

I point out that a magnetotransport theory on the basis of the fluctuation exchange (FLEX) approximation, which is proposed in order to explain anomalous transport properties in the normal state of high-$T_{\rm c}$ cuprate superconductors, is not compatible with the Fermi liquid theory and that the anomaly obtained there ascribes to the inconsistency of the approximation.Comment: 2 pages(REVTEX.sty

A Diagrammer's Note on Superconducting Fluctuation Transport for Beginners: I. Conductivity and Thermopower

A diagrammatic approach based on thermal Green function to superconducting fluctuation transport is reviewed keeping consistency with Ginzburg-Landau theory. The correct expression of the heat current vertex for Cooper pairs is clarified via Jonson-Mahan formula and Ward identities

Ward identities for charge and heat currents of particle-particle and particle-hole pairs

The Ward identities for the charge and heat currents are derived for particle-particle and particle-hole pairs. They are the exact constraints on the current-vertex functions imposed by conservation laws and should be satisfied by consistent theories. While the Ward identity for the charge current of electrons is well established, that for the heat current is not understood correctly. Thus the correct interpretation is presented. On this firm basis the Ward identities for pairs are discussed. As the application of the identity we criticize some inconsistent results in the studies of the superconducting fluctuation transport and the transport anomaly in the normal state of high-Tc superconductors

A diagrammer's note on DC conductivity of anisotropic Fermi liquids for beginners: Maebashi-Fukuyama formula and Taylor formula

Formal but exact DC conductivity formulae for anisotropic Fermi liquids are reviewed. One is the Maebashi-Fukuyama formula based on the Fermi-surface harmonics. The other is the Taylor formula based on the scattering eigenfunction. In comparison to these two formulae the current-vertex-correction in the fluctuation-exchange approximation is shown to be a bad vision caused by an inconsistent approximation.Comment: In v2 the review on the Taylor formula is adde

Ward identities for anisotropic Cooper pairs

Ward identities for anisotropic Cooper pairs are derived. These for nonlocal pairs have the same form as those for local pairs by employing the pair propagator with the form factor

Note on the Spin-Spin Relaxation Time in High-Tc Cuprate Superconductors

Recent experiments on the spin-spin relaxation time in high-Tc cuprate superconductors are discussed on the basis of the BCS-RPA theory.Comment: 3 pages(REVTEX.sty), 1 EPS figur

Entropic Approach to Error-Disturbance Tradeoff in Quantum Measurements

We discuss the relation between entropic uncertainty relations by Buscemi et al. and by Barchielli et al.Comment: To be published in JPSJ Short Not

Revival of Single-Particle Transport Theory for the Normal State of High-Tc Superconductors: II. Vertex Correction

The vertex correction for the electric current is discussed on the basis of the Fermi-liquid theory. It does not alter the qualitative description of the electric transport by the relaxation-time approximation in the case of the normal state of high-Tc superconductors. The failure of the transport theory employing the fluctuation-exchange (FLEX) approximation is pointed out. It becomes manifest by considering the Ward identity for the fluctuation mode.Comment: The footnote 10 has been added in the version

Aspect of Spin-Charge Separation due to Antiferromagentic Spin Fluctuations in Technically Nested 2D Metals

It is shown that the charge susceptibility in nearly half-filled two-dimensional (2D) metals, with technically nested Fermi surface, shows anomaly at the wavevector different from that for the spin susceptibility at low temperatures. Namely charge degrees of freedom behave there as if their ``Fermi surface" corresponded to that of ``holes" created in the Mott insulator. Such anomaly is caused by the Aslamazov-Larkin type contribution of 2D antiferromagnetic spin fluctuations. This phenomenon gives a possible clue to resolve the paradox of normal state properties of high-$T_{\rm c}$ cuprates {\it starting}\/ from the Fermi-liquid fixed point.Comment: 10 pages, revtex ver.3.0, hard copies of 4 figures which will be sent on reques