Thermal Transport Mechanisms in Emergent Ferroelectric Materials

To:                         All Interested Faculty, Students and Research Scientists

Announcing:        Ph.D. Dissertation Proposal by Sara Hoseini Makarem

Date:                     02/17/2025

Time:                     2:00 – 5:00 pm

Location:               MAE 346  

 

Committee:        Prof. Jon Ihlefeld 

                           Prof. Stephen McDonnell

                           Prof. Patrick Hopkins

                           Prof. Ethan Scott. 

Title                 Thermal Transport Mechanisms in Emergent Ferroelectric Materials

Abstract              

This research seeks to address critical questions regarding the thermal transport mechanisms in emerging ferroelectric materials, which are pivotal for the realization of energy-efficient neuromorphic computing and monolithic 3D architectures. This study focuses on understanding how dopant concentration, vacancy migration, and field-induced phase transitions influence phonon-mediated thermal conductivity in wurtzite and fluorite ferroelectrics, including aluminum nitride-based solid solutions as well as magnesium substituted zinc oxide and zirconium substituted hafnia. Given the inherently reduced thermal conductivity of these alloyed ferroelectrics and their reliance on precise thermal management for optimal functionality, this work aims to systematically investigate the impact of compositional and structural modifications on energy carrier dynamics. 

Utilizing optical pump-probe thermometry and infrared variable-angle spectroscopic ellipsometry (IR-VASE), this study aims to quantify thermal conductivity and phonon lifetimes in these novel materials and elucidate the effects of defect-induced scattering and strain-mediated phase transformations on phonon dynamics. By establishing direct correlations between the infrared optical response and thermal transport properties, this research will provide fundamental insights into phonon interactions and energy dissipation mechanisms. Specific efforts include examining the role of boron and magnesium doping in wurtzite ferroelectrics, assessing vacancy-driven phase evolution in fluorite ferroelectrics during the wake-up process, and evaluating the thermal conductivity of engineered substrates designed to optimize the performance of aluminum nitride-based ferroelectric materials. By integrating these insights, this study advances fundamental understanding of heat dissipation in next generation functional materials, facilitating their integration into nanoscale electronics, thermal circuits, and high-performance computing systems.

All interested persons are invited to attend.