Valentina Martelli

Physics

Valentina Martelli is an Italian researcher and lecturer at the Physics Institute of the University of São Paulo. She studies thermal, electrical, and thermoelectric transport phenomena in quantum materials under extreme conditions. Her research aims to elucidate the fundamental principles behind unusual heat transport phenomena, such as the thermal Hall effect.

After earning her bachelor’s, master’s, and doctoral degrees from the University of Florence, Valentina completed a postdoctoral fellowship at the Vienna University of Technology. She is currently conducting innovative experiments to understand how phonons—vibrations of the crystal lattice responsible for heat transfer in insulating solids—can be deflected by magnetic fields, a poorly understood phenomenon. Her project focuses on isolating the key parameters governing this property in simple, non-magnetic crystals, thereby contributing to theoretical advances in the field.

Open Calls

Science Call 7

Projects

What are the minimum conditions for a phonon to couple to a magnetic field and be deflected?
Science / Physics

In insulating solids, heat transfer occurs mainly through vibrations in the crystal lattice carried by quasiparticles called phonons. Lacking electric charge and spin, phonons are not expected to interact with magnetic fields. Over the past two decades, however, researchers have observed the thermal Hall effect in many materials: phonons are deflected in a magnetic field, creating a temperature difference. The fundamental mechanisms underlying this phenomenon remain poorly understood.

This project will systematically investigate the origin of the thermal Hall effect in simple, non-magnetic silicon oxide crystals. By performing heat transport experiments under extreme conditions of low temperature and high magnetic field, we aim to isolate the key parameters governing this property. This research will contribute to developing a comprehensive theoretical framework for understanding phonon-magnetic field interactions.

Amount invested

Grant Serrapilheira: R$ 350.000,00 (R$ 200.000,00 + R$ 150.000,00 optional bonuses aimed at the integration and training of individuals from underrepresented groups in science)