We report electric detection of the spin Peltier effect (SPE) in a bilayer consisting of a $\mathrm{Pt}$ film and a ${\mathrm{Y}}_3{\mathrm{Fe}}_5{\mathrm{O}}_{12}$ ($\mathrm{YIG}$) single crystal at the cryogenic temperature $T$ as low as 2 K based on a ${\mathrm{Ru}\mathrm{O}}_2\text{−}{\mathrm{Al}\mathrm{O}}_x$ on-chip thermometer film. By means of a reactive co-sputtering technique, we successfully fabricated ${\mathrm{Ru}\mathrm{O}}_2\text{−}{\mathrm{Al}\mathrm{O}}_x$ films having a large temperature coefficient of resistance of approximately $100\mathrm{\%}{\text{K}}^{-1}$ at around $2\text{K}$. By using the ${\mathrm{Ru}\mathrm{O}}_2\text{−}{\mathrm{Al}\mathrm{O}}_x$ film as an on-chip temperature sensor for a $\mathrm{Pt}$/$\mathrm{YIG}$ device, we observe a SPE-induced temperature change on the order of sub-$\text{μ}\text{K}$, the sign of which is reversed with respect to the external magnetic field $B$ direction. We found that the SPE signal gradually decreases and converges to zero by increasing $B$ up to $10\text{T}$. The result is attributed to the suppression of magnon excitations due to the Zeeman-gap opening in the magnon dispersion of $\mathrm{YIG}$, whose energy much exceeds the thermal energy at 2 K.

中文翻译：

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aRuO2−AlOxon 芯片测温仪检测低温自旋珀耳帖效应

我们报告了双层中自旋珀耳帖效应（SPE）的电检测，该双层由$铂$电影和一个${\mathrm{是}}_3{铁}_5{\mathrm{氧}}_{12}$（$\mathrm{伊格}$）低温下的单晶$\mathrm{时间}$低至 2 K 基于${茹\mathrm{氧}}_2\text{-}{铝\mathrm{氧}}_X$片上温度计薄膜。通过反应共溅射技术，我们成功制备了${茹\mathrm{氧}}_2\text{-}{铝\mathrm{氧}}_X$具有大电阻温度系数的薄膜大约为$100\mathrm{\%}{\text{K}}^{-1}$大约$2\text{K}$。通过使用${茹\mathrm{氧}}_2\text{-}{铝\mathrm{氧}}_X$薄膜作为片上温度传感器$铂$/$\mathrm{伊格}$设备中，我们观察到 SPE 引起的温度变化约为亚量级$\text{μ}\text{K}$，其符号相对于外部磁场相反$乙$方向。我们发现SPE信号逐渐减小并通过增加而收敛到零$乙$取决于$10\text{时间}$。该结果归因于磁振子色散中的塞曼能隙开放而抑制了磁振子激发$\mathrm{伊格}$，其能量远超过 2 K 时的热能。