Affiliation:
1. CAS Key Laboratory of Strongly coupled Quantum Matter Physics and Department of Physics University of Science and Technology of China Hefei Anhui 230026 P. R. China
2. Analytical and Testing Center Chongqing University Chongqing 401331 P. R. China
3. College of Physics and Center of Quantum Materials & Devices Chongqing University Chongqing 401331 P. R. China
4. Interdisciplinary Center for Fundamental and Frontier Sciences Nanjing University of Science and Technology Jiangyin Jiangsu 214443 P. R. China
Abstract
AbstractFull‐Heusler alloys (fHAs) exhibit high mechanical strength with earth‐abundant elements, but their metallic properties tend to display small electron diffusion thermopower, limiting potential applications as excellent thermoelectric (TE) materials. Here, it is demonstrated that the Co‐based fHAs Co2XAl (X= Ti, V, Nb) exhibit relatively high thermoelectric performance due to spin and charge coupling. Thermopower contributions from different magnetic mechanisms, including spin fluctuation and magnon drag are extracted. A significant contribution to thermopower from magnetism compared to that from electron diffusion is demonstrated. In Co2TiAl, the contribution to thermopower from spin fluctuation is higher than that from electron diffusion, resulting in an increment of 280 µW m−1 K−2in the power factor value. Interestingly, the thermopower contribution from magnon drag can reach up to ‐47 µV K−1, which is over 2400% larger than the electron diffusion thermopower. The power factor of Co2TiAl can reach 4000 µW m−1 K−2which is comparable to that of conventional semiconducting TE materials. Moreover, the corresponding figure of meritzTcan reach ≈0.1 at room temperature, which is significantly larger than that of traditional metallic materials. The work shows a promising unconventional way to create and optimize TE materials by introducing magnetism.
Funder
National Natural Science Foundation of China
Subject
General Physics and Astronomy,General Engineering,Biochemistry, Genetics and Molecular Biology (miscellaneous),General Materials Science,General Chemical Engineering,Medicine (miscellaneous)
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献