Numerical study of p-wave superconductivity in Sr2RuO4

physics;superconductivity

Roberts, Kevin J

关键词: physics;    superconductivity;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/78355/ROBERTS-DISSERTATION-2015.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This thesis contains detailed numerical studies of the superconducting stateof Sr2RuO4. This material's magnetic response displays hc=4e periodicity inmultiply connected samples, a striking departure from hc=2e periodicity of theLittle-Parks effect. One likely explanation for this is that, instead of the Cooperpairs existing in a spin-singlet state as in most conventional superconductors, thepairs form in an l = 1, or p-wave, angular momentum state. The additional spindegree of freedom offered by this angular momentum state allows the formationof half-quantum vortices possessing half of the usual flux quantum.In Chapter 1, I briefly review p-wave superconductivity and see how it supportshalf-quantum vortices. In Chapter 2, I review the conventional Ginzburg-Landau formalism for treating superconductivity. We then extend this formalismto treat p-wave superconductivity. In Chapter 3, I discuss the numericalmethods used to solve the coupled Ginzburg-Landau-Maxwell equations for themodel. In Chapter 4, I present numerical solutions of the Ginzburg-Landauequations for the proposed model in realistic geometries and show that the datacan be simulated using physically reasonable parameters. I also analyze animportant alternative explanation to the presence of half-flux states involvinginteger vortices penetrating the walls of the sample. In Chapters 6 and 7, Ipresent analyses of measurements of magnetoresistance oscillations in Sr2RuO4including evidence of phase-shift due to Abrikosov vortices.