在低于和高于临界温度$T_c$的铜氧化物超导体的准粒子（qp）色散关系的重整化有着巨大的兴趣，因为它能够确定的波动谱的qp耦合。角分辨光电子能谱（ARPES）的一个显著发现是在qp谱中的一个尖锐的低能特征（LEF），它远低于超导能隙，但其能量与$T_c$成比例地增加，而其强度在低于$T_c$时急剧增加。这个意想不到的特性需要与$d$波超导性相协调。在这里，我们提出了一个定量分析的ARPES数据从Bi $_2$ Sr $_2$ CaCu $_2$ O $_{8+δ}$（Bi 2212）使用Eliashberg方程表明，qp散射率由于远离Cu-O平面的前向散射杂质被修改的能隙低于$T_c$，并显示为LEF。这也是分析ARPES数据以揭示促进超导性的波动谱的必要步骤。
英文摘要：
There is an enormous interest in renormalization of quasi-particle (qp) dispersion relation of cuprate superconductors both below and above the critical temperature $T_c$ because it enables determination of the fluctuation spectrum to which the qps are coupled. A remarkable discovery by angle-resolved photoemission spectroscopy (ARPES) is a sharp low energy feature (LEF) in qp spectra well below the superconducting energy gap but with its energy increasing in proportion to $T_c$ and its intensity increasing sharply below $T_c$. This unexpected feature needs to be reconciled with $d$-wave superconductivity. Here, we present a quantitative analysis of ARPES data from Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ (Bi2212) using Eliashberg equations to show that the qp scattering rate due to the forward scattering impurities far from the Cu-O planes is modified by the energy gap below $T_c$ and shows up as the LEF. This is also a necessary step to analyze ARPES data to reveal the spectrum of fluctuations promoting superconductivity.
The vortex transport entropy in the mixed state of the cuprate superconductors YBa$_2$Cu$_3$O$_{7-δ}$ and Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ at the maximum Nernst or Ettingshausen signal below $T_c$ is discussed. The vortex transport entropy per CuO$_2$ double layer in the cuprate epitaxial films is found to be close to the Boltzmann constant.
Two-Orbital Model Explains the Higher Transition Temperature of the Single-Layer Hg-Cuprate Superconductor Compared to That of the La-Cuprate Superconductor
Nature of the quantum insulator to superconductor and superconductor to normal state transitions in cuprate superconductors
本文用量子临界现象的标度理论详细分析了La $_{2-x}$ Sr $_{x}$ CuO $_{4}$，Y $_{0.8}$ Ca $_{0.2}$-123，Tl-1212和Tl-2201的各种超导性质。我们的结果包括：实验数据是完全符合的2D绝缘体到超导体（ISQ）的过渡在欠掺杂的限制。量子临界性质似乎是相当于那些肮脏的2D玻色子系统与长程库仑相互作用。与以前的证据一起，这种转变似乎是铜酸盐超导体的一般特征。3D超导体到正常态的量子跃迁（SNQ）被证明不那么独特。需要更多的实验数据来明确地解决这种转变的性质。
Since their experimental discovery in 1989, the electron-doped cuprate superconductors have presented both a major challenge and a major opportunity. The major challenge has been to determine whether these materials are fundamentally different from or essentially similar to their hole-doped counterparts; a major opportunity because answering this question would strongly constrain the possible explanations for what is the essential physics that leads to high temperature superconductivity in the cuprates, which is still not agreed upon. Here we argue that experimental results over the past 30 ye…
We propose two possible new compounds, Ba$_2$CuO$_2$Fe$_2$As$_2$ and K$_2$CuO$_2$Fe$_2$Se$_2$, which hybridize the building blocks of two high temperature superconductors, cuprates and iron-based superconductors. These compounds consist of square CuO$_2$ layers and antifluorite-type Fe$_2$X$_2$ (X=As,Se) layers separated by Ba/K. The calculations of binding energies and phonon spectrums indicate that they are dynamically stable, which ensures that they may be experimentally synthesized. The Fermi surfaces and electronic structures of the two compounds inherit the characteristics of both cuprat…
Recent advances in the development of Josephson scanning tunneling spectroscopy (JSTS) have opened a new path for the exploration of unconventional superconductors. We demonstrate that the critical current, $I_c$, measured via JSTS, images the spatial form of the superconducting order parameter in $d_{x^2-y^2}$-wave superconductors around defects and in the Fulde-Ferrell-Larkin-Ovchinnikov state. Moreover, we show that $I_c$ probes the existence of phase-incoherent superconducting correlations in the pseudo-gap region of the cuprate superconductors, thus providing unprecedented insight into it…
The correlation between the charge-order wave vector Q_{CD} and second-neighbor hopping t' in cuprate superconductors is studied based on the t-t'-J model. It is shown that the magnitude of the charge-order wave vector Q_{CD} increases with the increase of t', and then the experimentally observed differences of the magnitudes of the charge-order wave vector Q_{CD} among the different families of cuprate superconductors at the same doping concentration can be attributed to the different values of t'.
Within the spin-fermion model for cuprate superconductors, the influence of the intersite Coulomb interactions $V_2$ and $V_2'$ between holes located at the next-nearest-neighbor oxygen ions of CuO$_2$ plane on the implementation of the d_{x^2-y^2}-wave pairing is studied. It is shown that d-wave pairing can be suppressed only for unphysically large values of $V_2$ and $V_2'$.
We report the pressure effect in Bi2Sr2Ca2Cu3O10+δ (Bi-2223) single crystal with a small amount of intergrowth of Bi2Sr2CaCu2O8+δ (Bi-2212). Their superconducting transition temperatures Tcs showed a domelike shape as a function of pressure, which showed a good agreement with the general relation between the carrier concentration and Tc. Our experimental results indicate that high pressure can induce effective carrier doping into the multilayered high-Tc cuprate superconductor
Nature of extrinsic and intrinsic self-trapping (ST) of charge carriers in cuprates have been studied theoretically. The binding energies and radii of the extrinsic and intrinsic large polarons and bipolarons in cuprates are calculated variationally using the continuum model and adiabatic approximation. We have shown that the extrinsic and intrinsic three-dimensional (3D) large bipolarons exist in underdoped cuprates at $η=\varepsilon_{\infty}/\varepsilon_0<0.127$ and $η<0.138$, respectively [where $\varepsilon_{\infty}$ ($\varepsilon_0$) is the optic (static) dielectric constant].
Studying angle-dependent magnetoresistance oscillations of cuprate superconductors in a model with antiferromagnetic reconstruction and magnetic breakdown
The renormalization of the electrons in cuprate superconductors is characterized by the kink in the quasiparticle dispersion. Here the bilayer coupling effect on the quasiparticle dispersion kink in the electron-doped bilayer cuprate superconductors is studied based on the kinetic-energy-driven superconductivity. It is shown that the kink in the quasiparticle dispersion is present all around the electron Fermi surface, as the quasiparticle dispersion kink in the single-layer case. However, in comparison with the corresponding single-layer case, the kink effect in the quasiparticle dispersion a…
By solving the Bogoliubov-de Gennes equations for a $d$-wave superconductor, we explore how the interplay between disorder and the orbital depairing of an external magnetic field influences the superconductor-metal transition of the hole-overdoped cuprates. For highly disordered systems, we find granular Cooper paring to persist above the critical field where the superfluid stiffness goes to zero. We also show that because the vortices are attracted to regions where the superconducting pairing is already weak, the Caroli-de Gennes-Matricon zero-bias peak in the local density of states at the v…
