Radio Frequency Behaviour of Pit-Processed Bi(2223) Tapes.

We have studied the response of long superconducting (Bi,Pb)[sub 2]Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub 10] based conductors fabricated by the Oxide Powder In Tube method when exposed to a radiofrequency magnetic field excitation. In particular, we have characterized their properties when employed as a part of L-C resonators typical of pick-up coil devices in Magnetic Resonance Imaging. In these conditions, Bi(2223) conductors cooled down to 77 K have shown superior properties compared to already optimized copper based devices: tri-dimensional superconducting pick-up coils conceived for a resonance frequency between 6 and 9 MHz present an improvement of the quality factor Q by more than an order of magnitude, and an increase of the signal-to-noise ratio by a factor larger than three. This promising result opens new perspectives for Bi-based conductors in the field of the detection of weak high frequency signals. [ABSTRACT FROM AUTHOR]