Traditionally, theoretical models used to study these systems have operated on timescales that are much faster than those observed experimentally, making it challenging to align the two.

The new modeling technique developed by the Finnish and Polish research team addresses this issue. They investigated a setup in which a benzene dithiol molecule is connected to copper electrodes and interacts with light within a cavity. Thanks to the innovative theoretical approach, the researchers were able to achieve a timescale that is experimentally relevant for examining molecular-level phenomena.

"Our theoretical results show that the molecular junction we studied can produce significant light emission and generate high harmonic frequencies," explains Dr. Riku Tuovinen, a senior lecturer at the University of Jyväskylä.

Interestingly, the way these effects occur is more akin to what has been observed in solid-state materials rather than in atomic or molecular systems.

"Additionally, we found that the symmetries associated with the setup can either suppress or enhance certain light frequencies, suggesting that this system could potentially be used as a switch or amplifier in molecular electronics," Tuovinen adds.

A Quantum Pump at the Molecular Level

The researchers describe the setup they examined as a type of quantum pump at the molecular level.

"Just as the efficiency of the ancient Archimedean screw depends on its tilt angle and thread pitch, the efficiency of molecular quantum pumps depends on the magnitude and phase difference of the driving voltages," Tuovinen elaborates.

This novel concept of a molecular quantum pump not only advances the understanding of electron movement in molecular junctions but also opens up new possibilities for the development of highly efficient electronic components in the future. The researchers' findings represent a significant step forward in the quest to harness the unique properties of molecules for technological applications.

HT