Admittance of Atomic and Molecular Junctions and Their Signal Transmission

作者：Sakai Akira^*

来源：Micromachines, 2018, 9(7): 320.

DOI：10.3390/mi9070320

• atom-sized contacts of metals
• single-atom contacts
• molecular junctions
• signal transmission
• conductance
• admittance

Atom-sized contacts of metals are usually characterized by their direct current (DC) conductance. However, when atom-sized contacts are used as device interconnects and transmit high frequency signals or fast pulses, the most critical parameter is not their DC conductance but their admittance Y (w), in particular its imaginary part ImY (w). In this article, I will present a brief survey of theoretical and experimental results on the magnitude of Y (w) for atom-sized contacts of metals. Theoretical contact models are first described and followed by numerical evaluation of ImY (w) based on these models. As for experiments on Y (w), previous experiments conducted under time-varying biases are surveyed, and then the results of direct signal transmission through atom-sized contacts are discussed. Both theoretical and experimental results indicate that ImY (w) is negligibly small for typical atom-sized contacts for signal frequencies up to 1 GHz.

• 出版日期2018-7