Thermoelectrics & Topology - E. Cheng
Thermoelectric effects enable the direct conversion of heat into electricity and vice versa, presenting promising solutions for power generation and solid-state cooling. Additionally, studying thermoelectric transport properties is crucial for exploring the complex energy scales associated with mobile quasiparticles and for understanding the fundamental interplay involving charge, lattice, spin, and topology in emerging topological materials.
This group primarily focuses on two research directions. The first involves the search and design of high-performance thermoelectric materials by examining their intrinsic electronic structures and phonon dispersions, and understanding how these factors influence electrical and thermal transport properties, with an emphasis on their single-crystalline forms. Additionally, we aim to explore emerging topologically non-trivial materials for exotic thermoelectric energy conversion, particularly the longitudinal and transverse thermoelectric responses under a magnetic field.
The second focus is on studying the interplay of charge, lattice, and spin in magnetic topological materials (e.g. Kagome systems, unconventional antiferromagnets) by examining their anomalous transport properties—such as the anomalous Hall, Nernst, and thermal Hall effects—alongside theoretical inputs. Beyond temperature and magnetic fields, techniques like strain will be used to tune crystal symmetry, allowing us to explore how symmetry breaking affects transport properties, magnetic structures, electronic band structures, and topological phase transitions, ultimately guiding innovative strategies for enhancing thermoelectric performance.
The group possesses a robust background in crystal growth and in measuring transport properties of solid materials. To accomplish our goals, we will foster extensive collaborations in microstructure characterization, magnetic structure measurements, and both theoretical and experimental investigations of electronic band structure. We welcome new members and collaborators who share our enthusiasm for exploring thermoelectric materials and topology. If you're interested in joining us or learning more about our work, please feel free to reach out!