Resistance anomalies in mesoscopic superconducting Al structures

We show that the recently reported anomalous resistance peaks near the superconducting transition of quasi-one-dimensional mesoscopic Al structures can be induced by applying either radio-frequency radiation or a sufficiently high dc current. The nomnonotonic R(T) curves can be linked to damages in the voltage-current characteristics below the superconducting transition. The observed dependence on the position of the voltage probes is consistent with recent theoretical calculations which interpret the anomalies in terms of the charge imbalance near phase-slip centers created at specific spots on the sample.