Quantum Engineered Thermoelectric Applications

Since its discovery in 19th century, the magnetic thermoelectric effect, known as “anomalous Nernst effect (ANE)” has been studied from basic science point of view but thought to have little practical value owing to its small magnitude. Yet recently, fascinating topological states that hide inside seemingly ordinary materials has been found to boost the ANE and brought it into the realm of technological innovation. A typical example is the Weyl magnet that shows surprisingly large ANE, letting us envision fundamentally new designs of thermoelectric devices that reshape the traditional paradigm based on the Seebeck effect. In this project, we fabricate thermoelectric modules and heat flux sensors using newly discovered topological magnets and explore the route to their commercialization.

Fig. 1 Seebeck effect (a) and Nernst effect (b) have the longitudinal and the transverse geometries between the voltage and temperature difference, respectively.

Fig. 2 Conventional thermopiles based on the Seebeck effect (a) and the newly designed thermopiles based on the anomalous Nernst effect (b), respectively.  In comparison with the pillar structure using p- and n-type semiconductors for the conventional thermoelectronics, the thermopile structure using the anomalous Nernst effect may be so simple as e.g. a film-type (yellow) deposited on a flexible substrate (b)



新技術説明会講演「磁性材料を用いた革新的熱電変換技術とその熱電モジュール・熱流センサー応用 」youtube
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Seebeck and Nernst.jpg