Switches are omnipresent in all electronic de- vices. Miniaturization reduced the size of switches down to atomic dimensions. While on-surface tip-tuned molecular switches have recently been widely studied, atomic switches have received much less attention despite the fact that they could, in addition to the size, reduce also the switching times by orders of magnitude by tuning directly their electronic, rather than atomic states. We have studied an ultra-fast tip-tuned conductance switch which can switch reversibly and repeatably by ap- plied bias. The switch is realized by an oxygen adatom supported on rutile TiO2 surface whose redox state can be switched between -1, -2, or 0, the former being conducting, the latter two nonconducting. Advanced simulations suggest that for virtually identical current-bias traces several mechanisms, such as discharge/recharge via a state of a nearby polaron or via a highly energetically unfavorable neutral redox state are involved.
|Journal Of Physical Chemistry C
|Accepted/In press - 2 Nov 2021