Terahertz charge dynamics of nanometals in liquids

About the Project

Supervisory Team: Fabio Novelli

This PhD investigates the electronic behaviour of metal nanoparticles in liquid environments. Using advanced terahertz spectroscopy, you will reveal how particle size, shape, and surroundings govern charge transport. The results will advance fundamental understanding with direct relevance to light harvesting, photonics, and catalytic technologies.

How do electrons move when metals shrink to the nanoscale and are dispersed in liquids? At this scale, conduction is profoundly altered: energy levels become quantum-confined, scattering is dominated by surfaces, and ligands mediate exchange across the metal–liquid interface. These effects underpin plasmonic light harvesting, liquid photonics, photochemistry, and catalysis, yet direct measurements of nanometal conductivity in realistic liquid environments are missing. This PhD project tackles that challenge by advancing terahertz (THz) spectroscopy driven by amplified laser pulses. You will quantify how electron transport evolves with nanoparticle size (from ultrasmall <5 nm, where confinement dominates, to ~100 nm, where bulk-like behaviour re-emerges), shape (spheres, rods, core–shell), and ligand chemistry. By comparing different dispersion environments, you will disentangle intrinsic nanoparticle behaviour from solvent-induced effects, establishing a systematic picture of charge transport in colloidal nanometals.

The project [1] builds on recent breakthroughs in THz spectroscopy: high-precision methods able to resolve refractive index changes as small as 0.01% in aqueous solutions [2], and contact-free retrieval of the conductivity of thin-film gold in quantitative agreement with electrical methods [3]. You will extend these advanced tools to nanoparticle dispersions, combining equilibrium and pump–probe experiments to reveal confined transport and ultrafast carrier dynamics.

You will be trained in ultrafast optics, terahertz instrumentation, nanoparticle handling, data analysis, and scientific communication. The outcome will be a new experimental framework for mapping electron dynamics in nanometals under realistic liquid-phase conditions — knowledge essential for future energy, photonic, and catalytic technologies.

[1] https://gepris.dfg.de/gepris/projekt/509442914?language=en

[2] https://doi.org/10.1364/OE.510393

[3] https://www.mdpi.com/1996-1944/17/16/3942

Entry Requirements

A very good undergraduate degree (at least a UK 2:1 honours degree, or its international equivalent).

Closing date: 31 August 2026. Applications will be considered in the order that they are received, the position will be considered filled when a suitable candidate has been identified.

Funding: We offer a range of funding opportunities for both UK and international students, including Bursaries and Scholarships. For more information please visit PhD Scholarships | Doctoral College | University of Southampton Funding will be awarded on a rolling basis, so apply early for the best opportunity to be considered.

How To Apply

Apply online: Search for a Postgraduate Programme of Study (soton.ac.uk)

• Programme type: Research
• Academic year: 2026/27
• If you will be full time or part time
• Faculty: Engineering and Physical Sciences

Search for programme PhD Physics (7089)

Please add the name of the supervisor in section 2 of the application.

Applications should include:

• your CV (resumé)
• 2 academic references
• degree transcripts/ certificates to date
• English language qualification (if applicable)

For further information please contact: feps-pgr-apply@soton.ac.uk