@article{oai:oist.repo.nii.ac.jp:00001885,
 author = {Akazawa, Masatoshi and Shimozawa, Masaaki and Kittaka, Shunichiro and Sakakibara, Toshiro and Okuma, Ryutaro and Hiroi, Zenji and Lee, Hyun-Yong and Kawashima, Naoki and Han, Jung Hoon and Yamashita, Minoru},
 issue = {4},
 journal = {Physical Review X},
 month = {Dec},
 note = {We investigate the thermal-transport properties of the kagome antiferromagnet Cd-kapellasite (Cd-K). We find that a field-suppression effect on the longitudinal thermal conductivity K-xx, sets in below approximately 25 K. This field-suppression effect at 15 T becomes as large as 80% at low temperatures, suggesting a large spin contribution  [Formula: see text] in K-xx. We also find clear thermal Hall signals in the spin liquid phase in all Cd-K samples. The magnitude of the thermal Hall conductivity K-xy shows a significant dependence on the sample's scattering time, as seen in the rise of the peak K-xy value in almost linear fashion with the magnitude of K-xx. On the other hand, the temperature dependence of K-xy is similar in all Cd-K samples; K-xy shows a peak at almost the same temperature of the peak of the phonon thermal conductivity [Formula: see text] which is estimated by K-xx, at 15 T. These results indicate the presence of a dominant phonon thermal Hall [Formula: see text] at 15 T. In addition to [Formula: see text], we find that the field dependence of K-xy at low fields turns out to be nonlinear at low temperatures, concomitantly with the appearance of the field suppression of K-xx, indicating the presence of a spin thermal Hall  [Formula: see text] at low fields. Remarkably, by assembling the K-xx dependence of  [Formula: see text] data of other kagome antiferromagnets, we find that, whereas  [Formula: see text] stays a constant in the low-K-xx region, [Formula: see text] starts to increase as K-xx does in the high-K-xx region. This K-xx dependence of  [Formula: see text] indicates the presence of both intrinsic and extrinsic mechanisms in the spin thermal Hall effect in kagome antiferromagnets. Furthermore, both  [Formula: see text] and  [Formula: see text], disappear in the antiferromagnetic ordered phase at low fields, showing that phonons alone do not exhibit the thermal Hall effect. A high field above approximately 7 T induces  [Formula: see text], concomitantly with a field-induced increase of K-xx and the specific heat, suggesting a coupling of the phonons to the field-induced spin excitations as the origin of [Formula: see text].},
 title = {Thermal Hall Effects of Spins and Phonons in Kagome Antiferromagnet Cd-Kapellasite},
 volume = {10},
 year = {2020}
}