針對CeRu2Al10和CeOs2Al10,我們量測了27Al在0 K到300 K的核磁共振訊號。這兩種材料分別在27 K和29 K被觀察到有相變態的發生,我們的核磁共振實驗結果發現這兩個樣品在低溫的時候沒有磁貢獻的存在。這兩種材料都是屬於YbFe2Al10的結構,在這種結構裡鋁原子的晶格位置有五種,所以在核磁共振的譜線裡面我們可以觀察到五個不同的鋁的訊號。而在低溫的時候,我們從奈特位移觀察出熱激發行為的存在。從晶格鬆弛時間的量測我們也發現在費米面上有能隙的存在。綜合奈特位移和晶格鬆弛時間的量測資料,我們推論出在費米面上存在著一個贗能隙而不是一個真正的能隙,而且我們所計算出的能隙大小跟非彈性中子散射實驗所得到的結果一致。

We report the 27Al NMR results of CeRu2Al10 and CeOs2Al10 at temperatures between 4 and 300 K. Both YbFe2Al10-type compounds have been of current interests due to heavy-fermion behaviors below transition temperatures T0 ~ 27 K and 29 K, respectively. At low temperatures, NMR observations show weak or zero magnetic ordering in both materials. For each material, five 27Al NMR resonance lines associated with five nonequivalent crystallographic Al sites are clearly resolved. For each Al site, a thermally activated response is found in low-temperature Knight shift data. The temperature-dependent spin-lattice-relaxation rate exhibits a rapid drop below T0, indicating the energy gaps over the Fermi surfaces. From the Knight shift and the relaxation-rate data, the gaps are found to be pseudogaps rather than real gaps and the extracted magnitudes of the gaps are in agreement with that from the inelastic neutron-scattering experiment.

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