Yen M.-CLee C.-JLiu K.-HPeng YLeng JTZU-HSUAN CHANGChang C.-CTamada KLee Y.-J.2023-06-092023-06-09202120411723https://www.scopus.com/inward/record.uri?eid=2-s2.0-85111135577&doi=10.1038%2fs41467-021-24762-w&partnerID=40&md5=29883f638c45ef9235de28d954308b23https://scholars.lib.ntu.edu.tw/handle/123456789/632296Field-induced ionic motions in all-inorganic CsPbBr3 perovskite quantum dots (QDs) strongly dictate not only their electro-optical characteristics but also the ultimate optoelectronic device performance. Here, we show that the functionality of a single Ag/CsPbBr3/ITO device can be actively switched on a sub-millisecond scale from a resistive random-access memory (RRAM) to a light-emitting electrochemical cell (LEC), or vice versa, by simply modulating its bias polarity. We then realize for the first time a fast, all-perovskite light-emitting memory (LEM) operating at 5 kHz by pairing such two identical devices in series, in which one functions as an RRAM to electrically read the encoded data while the other simultaneously as an LEC for a parallel, non-contact optical reading. We further show that the digital status of the LEM can be perceived in real time from its emission color. Our work opens up a completely new horizon for more advanced all-inorganic perovskite optoelectronic technologies. © 2021, The Author(s).indium tin oxide; perovskite; poly(methyl methacrylate); quantum dot; electrochemical method; inorganic compound; light intensity; perovskite; quantum mechanics; Article; electric conductivity; electrochemical analysis; electrochemistry; internet of things; light emitting memoryjournal article10.1038/s41467-021-24762-w342946992-s2.0-85111135577