Optically and redox switching molecular networks
In the continuation of our work on the design and synthesis of photo-addressable switch molecules (azobenzene derivatives) [K. Smaali et al., ACS Nano (2010)], we have integrated these molecules, and also redox molecules (thiophene derivatives), in organized gold nanoparticle networks and demonstrated a non-volatile optoelectronic memory effect [Y. Viero et al., J. Phys. Chem. C (2015)], a negative differential resistance effect [T. Zhang et al., J. Phys. Chem. C (2017), T. Zhang et al., Nanoscale Advances (2019)].
We use a network of molecularly linked gold nanoparticles to demonstrate the electrical detection (conductance variation) of a plasmon-induced isomerization (PII) of azobenzene derivatives (azobenzene bithiophene : AzBT). Possible PII mechanisms are discussed: electric field-induced isomerization, two-phonon process, plasmon-induced resonant energy transfer (PIRET), the latter being the most likely [D. Stievenard et al., Nanoscale (2018)].
Main coll. : P. Blanchard, J. Roncali (CNRS, Moltech-Anjou, U. Angers); M. Calame (EMPA & Univ. Basel, Switzerland), F. Cleri, C. Krzeminski (IEMN/Physique/NAMASTE), C.A. Nijhuis (Chem. Dept., NUS, Singapore).
Molecular networks for neuromorphic computing
We demonstrate optically-driven switchable logical operations in nanoparticles self-assembled networks of molecular switches (azobenzene derivatives) interconnected by Au nanoparticles. The complex non-linearity of electron transport and dynamics in these highly connected and recurrent networks of molecular junctions exhibit rich high harmonics generation (HHG) required for reservoir computing (RC) approaches. These results, without direct analogs in semiconductor devices, open new perspectives to molecular electronics in unconventional computing [Y. Viero et al., Adv. Func. Mater. (2018)].
Main coll. : M. Calame (EMPA & Univ. Basel, Switzerland).