CROSSOVER FROM 2-DIMENSION TO ONE-DIMENSION IN IN-SITU GROWN WIRES OF PB

Using a novel fabrication technique, we have studied the metal-insulator transition in in situ grown wires of Pb with cross-sectional areas as small as 10(-13) cm3. We find that as we cross over into the 1D regime, fluctuations dominate the superconducting transition. Although existing fluctuation models work well at the larger cross-sectional areas, there is systematic deviation as the wires become smaller. We speculate that this may be due to 1D Coulomb correlation effects.