Emerging materials with engineered electronic and optical properties are enabling the development of next-generation photonic and optoelectronic technologies. Low-dimensional carbon-based materials (such as atomic carbon wires, carbon dots, and carbon nanotubes), plasmonic nanostructures, hybrid systems, and materials with unconventional optical properties (e.g. epsilon-near-zero materials) exhibit unique light–matter interaction mechanisms, ultrafast carrier dynamics, and enhanced nonlinear optical responses. Understanding these properties is essential for the development of ultrafast photonic and optoelectronic devices, including all-optical switches, optical modulators, and integrated photonic components.

The thesis consists of an experimental investigation of the ultrafast optical response and nonlinear optical properties of these materials using ultrashort laser pulses (10–100 fs). Pump–probe spectroscopy and related time-resolved techniques will be employed to investigate photoexcitation and relaxation dynamics, including charge and energy transfer processes occurring on femtosecond to picosecond timescales, while nonlinear optical characterization will be performed using Z-scan and related methods.

The student will be involved in the development, alignment, and optimization of home-built optical setups, including the implementation of new experimental systems for ultrafast spectroscopy and nonlinear optical characterization based on the Z-scan technique. The activity provides hands-on experience with ultrafast laser sources, advanced optical instrumentation, and experimental data analysis.

The experimental activity takes place at the laboratories of the Physics Department of the Politecnico di Milano.

Contacts: Prof.ssa Margherita Zavelani-Rossi (02 2399 6069, margherita.zavelani@polimi.it)