Thermal conductivity of PrRh4.8B2, a layered boride compound
Yohei Kakefuda,
Kunio Yubuta,
Toetsu Shishido,
Akira Yoshikawa,
Shigeru Okada,
Hiraku Ogino,
Naoyuki Kawamoto,
Tetsuya Baba,
Takao Mori
Affiliations
Yohei Kakefuda
National Institute for Materials Science (NIMS), MANA, Namiki 1-1, Tsukuba 305-0044, Japan
Kunio Yubuta
Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Toetsu Shishido
Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Akira Yoshikawa
Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Shigeru Okada
Kokushikan University, 4-28-1 Setagaya, Tokyo 154-8515, Japan
Hiraku Ogino
Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Central 2, Umezono, Tsukuba 305-8568, Japan
Naoyuki Kawamoto
National Institute for Materials Science (NIMS), MANA, Namiki 1-1, Tsukuba 305-0044, Japan
Tetsuya Baba
National Institute for Materials Science (NIMS), MANA, Namiki 1-1, Tsukuba 305-0044, Japan
Takao Mori
National Institute for Materials Science (NIMS), MANA, Namiki 1-1, Tsukuba 305-0044, Japan
Transmission electron microscopy (TEM), specific heat, and thermal conductivity measurements were carried out for PrRh4.8B2 single crystals. PrRh4.8B2 takes an interesting layered crystal structure, where PrRh3B2 blocks are separated by metal Rh honeycomb layers. The existence of the Rh layers enhances the ferrimagnetic transition temperature. From area-selective picosecond thermoreflectance, the cross-plane thermal conductivity of PrRh4.8B2 is estimated to be 1.39 Wm−1 K−1, much lower than other layered borides like AlB2. Judging from the fine crystal structures obtained by TEM, phonon conduction is considered to be depressed due to random dispersion of Rh vacancy sites and two-dimensional nature of PrRh4.8B2.
