Finite-size effects in the low-temperature resistivity of CuCr films

The effect of finite sample size on the Kondo resistance anomaly has been explored in the CuCr system. The resistivity of thin CuCr films was studied as a function of width from 0.5 to 20 K. The magnitude of the Kondo anomaly is significantly depressed as the film width is reduced below 10 {μ}m. This length scale is consistent with the radius of the electron-spin correlation cloud, suggesting a crossover from two- to one-dimensional behavior. A concurrent decrease in the temperature of the resistivity maximum suggests a diminished interimpurity interaction strength.