Olivia Baxter (She/Her)

Current research project

Engineering and mapping entropy changes at the nanoscale in oxide materials

Electrocaloric materials are the focus of my PhD. Electrocalorics are the basis of a promising solid-state cooling technology that gets rid of the need for environmentally damaging gas refrigerants. Electrocaloric cooling is triggered by an electrical voltage, and fundamentally is due to an induced change in ‘entropy’, a measure of the ordering of the solid at a microscopic level. 

Ferroelectric materials are attractive candidates for electrocaloric cooling since their level of dipole ordering is known to be responsive to applied voltages, leading to significant induced temperature changes. Despite this, detailed knowledge of the origins of electrocaloric cooling at the microscopic level are still hotly debated. This is made even more challenging by the fact that many reports of electrocaloric performance are inferred from measurements of electrical properties and not true temperature measurements. 

My PhD project aims to use a cutting-edge technique known as Scanning Thermal Microscopy (SThM) to directly measure temperature changes at the nanoscale to better understand the microscopic behaviour of electrocaloric materials.

Biography

I graduated from Queen's University Belfast in 2020 with an MSci degree in Applied Mathematics and Physics. During my final year, I chose to complete an experimental physics master's project, which focused on characterising thermoelectric materials using scanning probe microscopy techniques. This led to me wanting to pursue further research in this area. I started my PhD at Queen's in October 2020.

Research interests

• Electrocaloric materials
• Ferroelectrics
• Microscopy