MSE Research Project Database

Understanding and monitoring the formation of ‘picocavities’

Project Leader: Eirini Goudeli
Primary Contact: Eirini Goudeli (
Keywords: nanostructured materials; nanotechnology
Disciplines: Chemical & Biomolecular Engineering

Picocavities are structures with a volume smaller than 1 nm3, forming an extreme class of optical localisation that enables optical experiments on the atomic scale. They are stable at cryogenic temperatures but are dynamically created and destroyed at room temperature.1 Stabilising such picocavities opens widespread possibilities for studying and exploiting light-molecule coupling in molecular interactions, chemical reactions, electron transfers and single-molecule electrochemistry.

In this project, the crystallinity dynamics and void formation mechanism between gold nanoparticles (NPs) and gold films spaced by a self-assembled monolayer (SAM) will be investigated by Molecular Dynamics simulations.2 The effect of the substrate crystal orientation, NP size and process temperature on their crystallinity and adhesion properties will be elucidated. Understanding the dynamics of NP-SAM-substrate interactions will set the basis for developing nanoscale nonlinear quantum optics on the single-molecule level. This work will help understanding the formation mechanism of picocavities and facilitate their monitoring and selective control which is important in photochemistry, photophysics, optomechanics and quantum information devices.

1. Benz, F., et al. “Single-molecule optomechanics in ‘picocavities’.” Science 354.6313 (2016): 726–729.

2. Goudeli, E., Pratsinis, S. “Crystallinity dynamics of gold nanoparticles during sintering or coalescence.” AIChE J. 62.2 (2016): 589–598.

Picocavity formation at the NP-SAM-substrate interface