[16p-Z19-1~23] 10.1 新物質・新機能創成（作製・評価技術）

▼ [16p-Z19-6] Efficient tuning of electronic, transport, and thermoelectric properties of Weyl semimetal Co₂MnAl_1-xSi_x composition-spread thin film

〇(P)Rajkumar Modak¹、Yoshio Miura¹、Shigenori Ueda¹、Ken-ichi Uchida^1,2,3、Yuya Sakuraba^1,4 (1.NIMS、2.IMR Tohoku Univ.、3.CSRN Tohuku Univ.、4.JST PRESTO)

キーワード：Spin-caloritronics, anomalous Nernst effect, Heusler Weyl semimetal

In this work we demonstrate a high throughput fabrication method for Heusler Weyl semimetal Co₂MnAl_1-xSi_x thin film with x variation from 0 to 1 on a single film by means of wedge shaped layer-by-layer deposition using combinatorial sputtering technique. A systematic tuning of Fermi energy level (E_F) and other transport and thermoelectric properties has been experimentally verified for the prepared composition-spread film. The observed result is compared with the results of single layered Co₂MnAl_1-xSi_x films with different compositions. Apart from the typical anomalous Nernst effect (ANE) measurement using Hall bars along composition gradient, a much simpler and faster approach has been discussed in terms of Lock-in thermography (LIT) and the measurement of anomalous Ettingshausen effect (AEE) which is the reciprocal effect of ANE. The combination of combinatorial deposition and LIT will accelerate the research on optimizing the best composition in Weyl semimetals and exploration of new materials to obtain giant ANE/AEE, which is essential to realize applications based on the transverse thermoelectric effects.