Electronic transport in underdoped YBa2Cu3O7-δ nanowires:: Evidence for fluctuating domain structures -: art. no. 087002

We have measured the transport properties of a series of underdoped YBa2Cu3O7-delta nanowires fabricated with widths of 100-250 nm. We observe large telegraphlike fluctuations in the resistance between the pseudogap temperature T-* and the superconducting transition temperature T-c, consistent with the formation and dynamics of a domain structure. We also find anomalous hysteretic steps in the current-voltage characteristics well below T-c.