Colorado State University
Sweeney, Mark Charles.
Vortex phases in type-I superconductors.
Degree: PhD, Physics, 2010, Colorado State University
Sufficiently thin films of type-I superconductor in a perpendicular magnetic field exhibit a triangular vortex lattice, while thick films develop an intermediate state. To elucidate what happens between these two regimes, precise numerical calculations have been made within Ginzburg-Landau theory at κ=0.5 and 0.25 for a variety of vortex lattice structures with one flux quantum per unit cell. The phase diagram in the space of mean induction and film thickness includes a narrow wedge in which a square lattice is stable, surrounded by the domain of stability of the triangular lattice at thinner films/lower fields and, on the other side, rectangular lattices with continuously varying aspect ratio. The vortex lattice has an anomalously small shear modulus within and close to the square lattice phase. Solutions of the Ginzburg-Landau equations have also been obtained for bulk systems and thin films for vortex lattices with one vortex but two flux quanta per square or triangular unit cell. These lattices of double fluxoid vortices are thermodynamically unstable in bulk in both type-I and type-II superconductors, as expected. In type-I films the situation is less clear, because the corresponding calculations for more complicated vortex lattice structures are not yet possible.
Advisors/Committee Members: Gelfand, Martin Paul (advisor), Mueller, Jennifer L. (committee member), Bradley, Richard M. (committee member), Field, Stuart B. (committee member).
Subjects/Keywords: superconductors; Vortex-motion; Thin films; Superconductivity; Superconductors – Magnetic fields
to Zotero / EndNote / Reference
APA (6th Edition):
Sweeney, M. C. (2010). Vortex phases in type-I superconductors. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/44985
Chicago Manual of Style (16th Edition):
Sweeney, Mark Charles. “Vortex phases in type-I superconductors.” 2010. Doctoral Dissertation, Colorado State University. Accessed April 13, 2021.
MLA Handbook (7th Edition):
Sweeney, Mark Charles. “Vortex phases in type-I superconductors.” 2010. Web. 13 Apr 2021.
Sweeney MC. Vortex phases in type-I superconductors. [Internet] [Doctoral dissertation]. Colorado State University; 2010. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/10217/44985.
Council of Science Editors:
Sweeney MC. Vortex phases in type-I superconductors. [Doctoral Dissertation]. Colorado State University; 2010. Available from: http://hdl.handle.net/10217/44985