Quantized Conductance in Pt Nanocontacts

The conductance of Pt nanocontacts has been measured at room temperature during the contact break of Pt relays. At low biases, the conductance histogram exhibits a broad peak around 1 G 0 , ( G 0 = 2 e 2 / h is the conductance quantum) in agreement with previous experimental results. Upon increasing the bias above 0.6 V, a well defined peak appears at 1.7 G 0 which decreases in height upon further increasing the bias. Except for its position at a non-quantized value, the observed 1.7 G 0 peak exhibits the same bias dependence as that of the quantized 1 G 0 peak of Au.