Large Enhancement of Thermoelectric Efficiency Due to a Pressure-Induced Lifshitz Transition in SnSe
| Autor: | Nishimura, T., Sakai, H., Mori, H., Akiba, K., Usui, H., Ochi, M., Kuroki, K., Miyake, A., Tokunaga, M., Uwatoko, Y., Katayama, K., Murakawa, H., Hanasaki, N. |
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| Rok vydání: | 2020 |
| Předmět: | |
| Zdroj: | Phys. Rev. Lett. 122, 226601 (2019) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevLett.122.226601 |
| Popis: | Lifshitz transition, a change in Fermi surface topology, is likely to greatly influence exotic correlated phenomena in solids, such as high-temperature superconductivity and complex magnetism. However, since the observation of Fermi surfaces is generally difficult in the strongly correlated systems, a direct link between the Lifshitz transition and quantum phenomena has been elusive so far. Here, we report a marked impact of the pressure-induced Lifshitz transition on thermoelectric performance for SnSe, a promising thermoelectric material without strong electron correlation. By applying pressure up to 1.6 GPa, we have observed a large enhancement of thermoelectric power factor by more than 100% over a wide temperature range (10-300 K). Furthermore, the high carrier mobility enables the detection of quantum oscillations of resistivity, revealing the emergence of new Fermi pockets at ~0.86 GPa. The observed thermoelectric properties linked to the multi-valley band structure are quantitatively reproduced by first-principles calculations, providing novel insight into designing the SnSe-related materials for potential valleytronic as well as thermoelectric applications. Comment: 13 pages, 4 figures |
| Databáze: | arXiv |
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