We have used a dc Superconducting QUantum Interference Device to measure the magnetic flux noise generated by the equilibrium vortex density fluctuations associated with the Kosterlitz-Thouless-Berezinskii (KTB) transition in an overdamped Josephson junction array. At temperatures slightly above the KTB transition temperature, the noise is white for f < f ξ and scales as 1/f for f > f ξ . Here f ξ ∝ ξ −z , where ξ is the correlation length and z is the dynamic exponent. Moreover, when all frequencies are scaled by f ξ , data for different temperatures and frequencies collapse on to a single curve.

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