ALGEBRAIC DECAY OF FLUXOID-DYNAMICS IN THE BSCCO HIGH-TC SUPERCONDUCTOR

From measurements of the complex ac-susceptibility between 3 Hz and 2 MHz on a dense ceramic cylinder in a field of 1 tesla the complex frequency-dependent penetration depth lambda(ac)(omega) is evaluated. A novel algebraic law, lambda(ac)2(omega, T) approximately (iomegatau0)-beta(T) is obtained, the exponent of which drops discontinuously to low values (beta less-than-or-equal-to 0.2) at the glass transition T(g) = 20 K and increases linearly to the conventional value beta = 1 at T(l) = 70 K. Above T(l) the dynamics indicates a vortex liquid (beta = 1) defining an intrinsic transition, which unlike the irreversibility line does not depend on external parameters like sample radius and observation time.