铜氧化物超导体中欠掺杂到过掺杂区域的费米速度和能隙速度的研究（英文）

The Fermi Velocityand Gap Velocity from Underdoping to Heavily Overdoping in Cuprate Superconductors

通过考虑赝能隙的影响,研究了铜氧化物超导体中从欠掺杂区域到过掺杂区域的费米速度和能隙速度随掺杂的变化关系。研究结果表明,费米速度VF随掺杂浓度几乎成线性变化,并随掺杂浓度的增加而增加,而能隙速度v2随着掺杂浓度的增加而减小,在重过掺杂区域降为零。并研究了掺杂的准粒子速度和能隙速度之比vF/v2随掺杂浓度的依赖关系。结果表明,vF/v2随着掺杂浓度的增加而增加。解释了vF/v2在重过掺杂铜氧化物超导体中迅速增加的现象。

By considering the pseudogap effect,the doping dependence of Fermi velocity and gap velocity in cuprate superconductors is studied from under doping to heavily overdoped region.Our results show that the Fermi velocity vFas a function of doping exhibits almost linear dependence,and it increases with the doping concentration increases from under doping to overdoping,while the gap velocity vF decreases with the doping concentration increase,and it reaches zero in heavily overdoped region.In particular,we have studied the doping dependence of the ratio of quasiparticle velocities normal and tangential to the Fermi surface at the nodes vF/v2.It is shown that vF/v2 increases with the doping concentration increasing.Moreover,we explain that vF/v2 has very rapidly increased upon the doping concentration increasing in heavily overdoped cuprate superconductors.