Critical scaling of third-harmonic transmissivity near the Bose-glass transition in YBa2Cu3O7 single crystals with columnar defects

The vortex dynamics in YBa2Cu3O7 single crystals with parallel columnar defects are investigated by studying the complex third-harmonic transmissivity (TH3). In the "one-loop" approximation, the dependence of TH3 on temperature, ac excitation frequency, dc magnetic field strength, and orientation can be consistently described in terms of a characteristic relaxation time (τ) and a crossover current density (j). Critical scaling laws for TH3 are derived and applied to the experimental data. The results are in excellent agreement with the Bose-glass theory. © 1995 The American Physical Society.