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arXiv · 2011.12660

Enhancement of giant refrigerant capacity in Ho$_{1-x}$Gd$_{x}$B$_{2}$ alloys (0.1 $\leq$ x $\leq$ 0.4)

Pedro Baptista de Castro·Kensei Terashima·Takafumi D Yamamoto·Suguru Iwasaki·Akiko T. Saito·Ryo Matsumoto·Shintaro Adachi·Yoshito Saito·Mohammed ElMassalami·Hiroyuki Takeya·Yoshihiko Takano
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Abstract

Intending to optimize the giant magnetocaloric properties of HoB$_{2}$, we synthesized and magnetocalorically characterized Ho$_{1-x}$Gd$_{x}$B$_{2}$(0.1 $\leq$ x $\leq$ 0.4) alloys. We found out that Gd enters stoichiometrically and randomly into the Ho site, leading to a Vegard-type structural change. The addition of spherical S$^{7/2}$ Gd$^{3+}$ moments prompts an enhancement in Curie temperature, a reduction in peak value of the magnetic entropy change while still being relatively high, and a broadening of the magnetic entropy change curves. The overall influence is a relatively high refrigerant capacity and relative cooling power, and an extension of the thermal working range to higher temperatures; thus, electing Ho$_{1-x}$Gd$_{x}$B$_{2}$(as potential candidates for cryogenic refrigeration applications.

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Pedro Baptista de Castro, Kensei Terashima, Takafumi D Yamamoto, Suguru Iwasaki, Akiko T. Saito, Ryo Matsumoto, Shintaro Adachi, Yoshito Saito, Mohammed ElMassalami, Hiroyuki Takeya, Yoshihiko Takano. 2020-11-25. Enhancement of giant refrigerant capacity in Ho$_{1-x}$Gd$_{x}$B$_{2}$ alloys (0.1 $\leq$ x $\leq$ 0.4). https://doi.org/10.1016/j.jallcom.2021.158881

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