Monolayer optical memory cells based on artificial trap-mediated charge storage and release.
Monolayer transition metal dichalcogenides are considered to be promising candidates for flexible and transparent optoelectronics applications due to their direct bandgap and strong light-matter interactions. Although several monolayer-based photodetectors have been demonstrated, single-layered optical memory devices suitable for high-quality image sensing have received little attention. Here we report a concept for monolayer MoS2optoelectronic memory devices using artificially-structured charge trap layers through the functionalization of the monolayer/dielectric interfaces, leading to localized electronic states that serve as a basis for electrically-induced charge trapping and optically-mediated charge release. Our devices exhibit excellent photo-responsive memory characteristics with a large linear dynamic range of ∼4,700 (73.4 dB) coupled with a low OFF-state current (<4 pA), and a long storage lifetime of over 104s. In addition, the multi-level detection of up to 8 optical states is successfully demonstrated. These results represent a significant step toward the development of future monolayer optoelectronic memory devices.
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Juwon
J
Lee
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Sangyeon
0000-0003-1765-3043
S
Pak
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Young-Woo
YW
Lee
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Yuljae
0000-0003-2976-0604
Y
Cho
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
John
0000-0002-1513-8622
J
Hong
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Paul
P
Giraud
Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan 44919, Republic of Korea.
Hyeon Suk
0000-0003-0495-7443
HS
Shin
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Stephen M
SM
Morris
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Jung Inn
0000-0002-3155-4327
JI
Sohn
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
SeungNam
S
Cha
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
Jong Min
JM
Kim