Low-temperature cotunneling electron transport in photo-switchable molecule-nanoparticle networks
Year: 2025
Type: article
Abstract: We report the temperature-dependent (4.2–300 K) electron transport properties (current–voltage) of photo-switchable two-dimensional arrays of gold nanoparticles (10 nm in diameter) functionalized by azobenzene derivatives. Under UV-light irradiation at 4.2 K, the azobenzene moieties are switched from the trans-to-cis isomers, leading to an increase of the current. In both conformations, at low temperature (<77 K) and low voltage (<1 V), the voltage- and temperature-dependent current behaviors show that electron cotunneling is the dominant transport mechanism. The number of cotunneling events Ncot slightly increases from ≈1.4 to 1.7 upon trans-to-cis isomerization of the azobenzenes. The nanoparticle Coulomb charging energy is not significantly modified (≈15 meV) by the azobenzene isomerization. This weak increase of Ncot is explained by the modest cis/trans current ratio (≤10) and the limited numbers of nanoparticle–molecule–nanoparticle junctions inserted between the two nanoscale electrodes (<50 nm apart) connecting the network.
Source: Journal of Applied Physics
DOI: 10.1063/5.0284541
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,500
Funder: Agence Nationale de la Recherche
Awards: G2518109393, G3727393138, G6702880738
OpenAlex ID: W4413288681
