rXXXX American Chemical Society A dx.doi.org/10.1021/nl201074a |Nano Lett. XXXX, XXX, 000–000 LETTER pubs.acs.org/NanoLett Piezotronic Nanowire-Based Resistive Switches As Programmable Electromechanical Memories

The concept of complementing field effect transistors (FETs)with two-terminal hysteretic resistive switches has recently attracted a great interest in implementing and scaling novel nonvolatile resistive memories15 for ultrahigh density mem-ory storage6,7 and logic applications8,9 with characteristics such as high-density, low cost, fast write/read accessing speed and long endurance/retention time.10 Notably, previous existing nonvolatile resistive memories are all based on electrically switchable resistance change10 by means of formation of con-ductive filaments,5,11 charge-transfer-induced conformational change,12 electrochemical processes,13 or field-assisted drift/ diffusion of charged ions3,4,6,14 in various oxides and ionic conductors.1517 These devices are electrically programmed and they are not suitable for direct interfacing with actuation/ triggering other than electrical inputs. For applications such as human-computer interfacing, sensing/actuating in nanorobo