Research On Abnormal Physical Properties Of Copper Oxide High-temperature Superconductors

The study of the anomalous physical properties of cuprate high-temperature superconductors has always been the central subject of high-temperature superconductivity research.This article is based on the t-J model,fermion-spin theory,and BCS theory,and compares the corresponding with corresponding experimental results.The superconducting mechanism,universal properties and Raman scattering electron spectrum of the cuprate high-temperature superconductor have been systematically studied,providing a possible physical explanation for these physical phenomena in cuprate high-temperature superconductors.In this paper,we mainly conducted an in-depth study on the“Effect of the nonmonotonic d-wave superconducting gap on the electronic Raman scattering of electron-doped cuprate superconductors”.We divide the research into two parts.The first part is a theoretical study of electron Raman scattering,and the second part is the derivation and explanation of the required theoretical framework.Therefore,a detailed discussion and research were carried out on the basis of these theories.For electron Raman scattering,our results showed novel features observed in Raman experiments on optimally doped and underdoped Bi-2212 compounds in B1g geometry can be explained by a strong fermionic self-energy due to the interaction with spin flfluctuations.In the following,we separately calculated the Raman intensity R???above and below Tc.In both cases,our results show that due to the increase in fermion self-energy,R???will gradually deviate from the Raman scattering intensity in the Fermi gas as the doping concentration decreases.Our results also show that the interaction in the final state will increase as the doping concentration decreases,and gradually convert the2?peak in the superconducting state to a pseudo-resonant mode below 2?.Our results of these studies are in good agreement with the experimental data of Bi-2212.We studyed the Raman scattering effect of non-monotonic d-wave superconducting gap on electron-doped cuprate superconductors by comparing with hole-doped cuprate high-temperature superconductors with pure d-wave SC gap.Our results showed that the electron Raman scattering of electron-doped cuprate superconductors is significantly different from that of hole-doped cuprate superconductors with pure d-wave SC gap.The non-monotonic d-wave SC gap of cuprate high-temperature superconductors is the main reason for the difference.There are three main different behaviors of electron Raman scattering spectra between electron-doped and hole-doped cuprate superconductors:1.the intensity of B1g and B_2gg spectra;2.the Raman peak position as a function of energy between B_1gg and B_2gg spectra;3.Energy asymptotic behavior of low-energy B1g spectrum.For electron-doped cuprate superconductors,the intensity of the B_2gg spectrum as a function of energy is larger than the B1_g spectrum,the Raman peak position of the B2_g spectrum is higher than the B1_g spectrum,and the low-energy spectrum of B_1gg as a function of energy increases linearly,rather than?³ energy dependence of hole-doped cuprate superconductors.The theoretical results of all these electron-doped cuprate superconductors are qualitatively consistent with the corresponding Raman scattering experimental data,and they are in sharp contrast to the case of hole-doped cuprate superconductors.