Fabrication and Microwave Responses of YBa₂Cu₃O_7-x Superconducting Thin-Film Nanobridges

Abstract

A 6-dimensional grand unified theory with the compact space having the topology of a real projective plane, i.e., a 2-sphere with opposite points identified, is considered. The space is locally flat except for two conical singularities where the curvature is concentrated. One supersymmetry is preserved in the effective 4d theory. The unified gauge symmetry, for example SU(5) , is broken only by the non-trivial global topology. In contrast to the Hosotani mechanism, no adjoint Wilson-line modulus associated with this breaking appears. Since, locally, SU(5) remains a good symmetry everywhere, no UV-sensitive threshold corrections arise and SU(5)-violating local operators are forbidden. Doublettriplet splitting can be addressed in the context of a 6d N = 2 super Yang-Mills theory with gauge group SU(6). If this symmetry is first broken to SU(5) at a fixed point and then further reduced to the standard model group in the above non-local way, the two light Higgs doublets of the MSSM are predicted by the group-theoretical and geometrical structure of the model.

Excimer laser patterning of superconducting BiSrCaCuO thin films

“…Electric device application of these films requires the patterning technique. These techniques have been studied by a variety of methods including ion beam etching for Y-123 films [8][9][10][11], chemical etching methods for Y-123 films [12][13][14][15][16] and for BSCCO films [17], excimer laser methods for Y-123 [18][19][20][21] and BSCCO films [22], and reactive etching [23]. Among these methods, the excimer laser etching technique may enable very precise etching of oxide superconductors and has the advantages of processing without heat degeneration.…”