Research On The Fermi Velocity Energy And Energy Gap Velocity Of Copper Oxide Superconductor Under-doped Into The Over-doped Region

In recent years,the research of superconducting materials,especially high-temperature superconducting materials,has always been one of the hotspots and difficulties in condensed matter physics.High-temperature superconducting materials represented by copper oxide high-temperature superconducting materials have a wide range of development prospects due to the high superconducting transition temperature,and high-temperature superconducting materials have been widely used in various industries.At present,although the superconducting mechanism of copper oxide high-temperature superconducting materials is not completely understood,such materials have been confirmed to be very different from conventional superconducting materials.The superconducting mechanism of traditional superconducting materials is electro-acoustic interaction,and the copper oxide high-temperature superconducting material is caused by the strong correlation effect between electrons and electrons.Therefore,how to deal with the strong electron-related effects in copper oxide superconducting materials is a difficult and important point in the study of such materials.In this paper,we use the Gutzwiller approximation,which can deal with the strong correlation effect between electrons,and get the reordered Hubbard model.Considering the impurity doping effect,the cost of the copper oxide superconductor from underdoped to overdoped region.The relationship between meter speed and energy gap velocity and doping.The first part of this article briefly explained how superconducting materials have been developed step by step until now.The materials containing copper oxide high-temperature superconductors were compared with the previously discovered superconducting materials that explain the mechanism of superconductivity by the BCS theory.Some persuasive evidence was found to describe the internal crystal structure of the copper oxide high-temperature superconductor,the characteristics of the internal patterns,and simply the extent to which it is currently being studied.In the second part of this paper,in order to efficiently describe the model of copper oxides in high-temperature superconducting materials under very low temperature conditions,we introduced the Hubbard model and used it to explain the strong coupling effect between electricity and electricity.With such a description,we can elicit the model we want.Regarding the interaction between electricity and electricity,we chose to use Gutzwiller's average field approximation theory to rearrange the Hamiltonian and do a deeper study.To thinking this pseudogap effect,the doping dependence of Fermi velocity and gap velocity in cuprate superconductors are studied from underd oping to heavily overdoped region.Our results show that the Fermi velocityas a function of doping exhibits almost linear dependence,and it increases with the doping concentration increases from underdoping to overdoping,while the gap velocitydecreases 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?₂.It is shown that?₂ increases with the doping concentration increasing.Moreover,we explain that?₂ has very rapidly increased upon the doping concentration increasing in heavily overdoped cuprate superconductors.