FLUX TRAPPING ON MULTI-SUPERCONDUCTING PHASE PAT12-C-60-RB COMPOSITE - LOW-FIELD MICROWAVE-ABSORPTION STUDY

The in-phase and out-of-phase low held microwave absorption (LFMA) sig nals in a PAT12(C-60)(0.05)Rb-x composite, consisting of superconducti ng granular Rb3C60 grains embedded in host poly(3-alkyltiophene) (PAT1 2) matrices, are investigated as functions of temperature and the inte nsity of trapped field. Temperature dependence of the peak field H-p o f the out-of-phase and in-phase LFMA obeys the relation H-p similar to {1-(T/T-c2)}(1/4) and H-p similar to{1-(T/T-cl)(4)}(1/2) respectively , where T-c2 (= 22 K) and T-cl (=26 K) is the critical temperature of respective phase. Threshold field of the flux trapping in the out-of-p hase and in-phase LFMA is nearly zero and 150 G respectively. These re sults support the previous models proposed for the origins of two phas es presented in the K-doped CP-C-60 composites. (C) 1997 Elsevier Scie nce Ltd.