rXXXX American Chemical Society A dx.doi.org/10.1021/nl2011966 |Nano Lett. XXXX, XXX, 000–000 LETTER pubs.acs.org/NanoLett Polar Charges Induced Electric Hysteresis of ZnO Nano/Microwire for Fast Data Storage

Ferroelectric random access memory 13 is attracting a great interest both in scientific research and industry applications for its low power consumption, faster reading/writing speed, and extremely large writing-erasing cycles compared to other mem-ory technologies, such as capacitors and transistor-coupled units made by lithography technique on silicon wafers.4,5 The advan-tages come from the spontaneous polarization dipoles in the cells of ferroelectric materials, which can be rapidly reversed by an electric field. However, as the size of a memory unit shrinks to submicrometer scale, the ferroelectric material would lose its ferroelectric property due to the surface screening effect, result-ing in lower storage density.68 As the traditional random access memory reaches the limit of the metaloxidesemiconductors, searching for new approach for fast reading-rewriting and high