  We report a simple and reproducible method to fabricate two metallic
electrodes made of different metals with a nanometer-sized gap. These
electrodes are fabricated by defining a pair of gold electrodes
lithographically and electrodepositing a second metal onto one of them. The
method enables the fabrication of pairs of metallic electrodes that exhibit
distinct magnetic properties or work functions. The utility of this technique
is demonstrated by making single-electron tunneling devices incorporating 2-nm
gold nanocrystals.
