$^{195}$Pt-NMR measurements of Pt nanoparticles with a mean diameter of 4.0 nm were performed in a high magnetic field of approximately $\mu_0 H = 23.3$ T to investigate the low-temperature electronic state of the nanoparticles. The characteristic temperature $T^*$, below which the nuclear spin-lattice relaxation rate $1/T_1$ deviates from the relaxation rate of the bulk, shows a magnetic-field dependence. This dependence supports the theoretical prediction of the appearance of discrete energy levels.

中文翻译：

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与量子尺寸效应相关的新型间隙行为的磁场依赖性

在大约 $\mu_0 H = 23.3 $ T 的高磁场中对平均直径为 4.0 nm 的 Pt 纳米粒子进行 $^{195}$Pt-NMR 测量，以研究纳米粒子的低温电子状态。特征温度 $T^*$，低于该温度，核自旋晶格弛豫率 $1/T_1$ 偏离体的弛豫率，显示出磁场依赖性。这种依赖性支持离散能级出现的理论预测。