Conduction Channel Transmissions of Atomic-Size Aluminum Contacts
نویسندگان
چکیده
We have determined the individual transmission coefficients of Al quantum point contacts containing up to six conduction channels. The determination is based on a comparison of the highly nonlinear current-voltage characteristics in the superconducting state with the predictions of the theory for a single channel superconducting contact. We find that at least two channels contribute to the transport even for contacts with conductance lower than the conductance quantum. [S0031-9007(97)03088-3]
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تاریخ انتشار 1997