Current-induced embrittlement of atomic wires.
Recent experiments suggest that gold single-atom contacts and atomic chains break at applied voltages of 1 to 2 V. In order to understand why current flow affects these defect-free conductors, we have calculated the current-induced forces on atoms in a Au chain between two Au electrodes. These forces are not by themselves sufficient to rupture the chain. However, the current reduces the work to break the chain, which results in a dramatic increase in the probability of thermally activated spontaneous fracture of the chain. This current-induced embrittlement poses a fundamental limit to the current-carrying capacity of atomic wires.
Todorov
T N
TN
School of Mathematics and Physics, The Queen's University of Belfast, Belfast BT7 1NN, United Kingdom. T.Todorov@qub.ac.uk
Hoekstra
J
J
Sutton
A P
AP