CRITICAL SCALING OF FREQUENCY-DEPENDENT MAGNETIC-SUSCEPTIBILITY IN YBA2CU3O7 SINGLE-CRYSTALS NEAR THE VORTEX-GLASS TRANSITION

A demonstration of critical scaling of the magnetic susceptibility in a YBa2Cu3O7 single crystal is performed for 350 frequencies (f) from 1 kHz to 2 MHz. Near the vortex-glass melting temperature T(M)(H) and i n the linear-response limit, the susceptibility chi = \chi\e(i(pi-phi( chi)) follows the scaling relations \chi\ approximately \1-(T/T(M))\nu /2 for f --> 0, \chi\ approximately f1/(2z) and phi(chi) = pi/4z for T --> T(M). The static and dynamic exponents (nu almost-equal-to 2/3 an d z almost-equal-to 3) as well as T(M)(H) are found to be in excellent agreement with our previous dc and ac transport measurements, lending strong support for a second-order phase transition.