Switching kinetics of a Cu2S-based gap-type atomic switch

Nanotechnology

Switching kinetics of a Cu₂S-based gap-type atomic switch

Alpana Nayak¹, Tohru Tsuruoka¹, Kazuya Terabe¹, Tsuyoshi Hasegawa¹ and Masakazu Aono¹

Published 11 April 2011 • IOP Publishing Ltd
Nanotechnology, Volume 22, Number 23 Citation Alpana Nayak et al 2011 Nanotechnology 22 235201

Abstract

The switching time of a Cu₂S-based gap-type atomic switch is investigated as a function of temperature, bias voltage, and initial off-resistance. The gap-type atomic switch is realized using a scanning tunneling microscope (STM), in which the formation and annihilation of a Cu-atom bridge in the vacuum gap between the Cu₂S electrode and the Pt tip of the STM are controlled by a solid-electrochemical reaction. Increasing the temperature decreases the switching time exponentially with an activation energy of about 1.38 eV. Increasing the bias voltage also shortens the switching time exponentially, exhibiting a greater exponent for the lower bias than for the higher bias. Furthermore, faster switching has been achieved by decreasing the initial off-resistance between the Cu₂S electrode and STM tip. On the basis of these results, we suggest that, in addition to the chemical reaction, the electric field in the vacuum gap plays a significant role in the operation of a gap-type atomic switch. This investigation advances our understanding of the operating mechanism of an atomic switch, which is a new concept for future electronic devices.