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 TM(H) and in the linear-response limit, the susceptibility χχeχi(π-φ) follows the scaling relations χ∼1-(T/TM)ν/2 for f→0, χ∼f1/(2z) and φχ=π/4z for T→TM. The static and dynamic exponents (ν2/3 and z3) as well as TM(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. © 1994 The American Physical Society.