Electron tunneling through a monolayer of small metal clusters investigated by scanning tunneling spectroscopy
نویسنده
چکیده
We have investigated the current-voltage characteristic of monolayers of seperated metal clusters of a size of 1.4 nm with a low-temperature ultrahigh vacuum scanning tunneling microscope. Apart from the usual charge-quantization phenomena, such as Coulomb blockade and staircase, negative differential resistance was observed by performing measurements at distinct locations on the cluster layers. The latter phenomenon can be understood by a “leakage” current to a neighboring cluster and a nonclassical behavior of the nanojunction capacitances caused by electron tunneling.
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