Kim, Jeong-Mok Kim, Seok-Jong Kang, Min-Gu Choi, Jong-Guk Lee, Soogil Park, Jaehyeon Van Phuoc, Cao Kim, Kyoung-Whan Kim, Kab-Jin Jeong, Jong-Ryul Lee, Kyung-Jin Park, Byong-Guk 2024-01-12T06:35:43Z 2024-01-12T06:35:43Z 2023-06-29 2023-06 2041-1723 https://pubs.kist.re.kr/handle/201004/79908 Spin Seebeck effect (SSE) refers to the generation of an electric voltage transverse to a temperature gradient via a magnon current. SSE offers the potential for efficient thermoelectric devices because the transverse geometry of SSE enables to utilize waste heat from a large-area source by greatly simplifying the device structure. However, SSE suffers from a low thermoelectric conversion efficiency that must be improved for widespread application. Here we show that the SSE substantially enhances by oxidizing a ferromagnet in normal metal/ferromagnet/oxide structures. In W/CoFeB/AlOx structures, voltage-induced interfacial oxidation of CoFeB modifies the SSE, resulting in the enhancement of thermoelectric signal by an order of magnitude. We describe a mechanism for the enhancement that results from a reduced exchange interaction of the oxidized region of ferromagnet, which in turn increases a temperature difference between magnons in the ferromagnet and electrons in the normal metal and/or a gradient of magnon chemical potential in the ferromagnet. Our result will invigorate research for thermoelectric conversion by suggesting a promising way of improving the SSE efficiency. English Nature Publishing Group Enhanced spin Seebeck effect via oxygen manipulation Article 10.1038/s41467-023-39116-x 1 Nature Communications, v.14, no.1 Nature Communications 14 1 Y scie scopus 001047512000032 Multidisciplinary Sciences Science & Technology - Other Topics Article