釹基燒綠石(Nd-pyrochlore)化合物具有磁矩分裂、八極級與自旋手性等新穎的物理現象。在本文中，我們使用中子粉末繞射、μSR技術和室內量測如熱容，磁化率等，對雙燒綠石化合物Nd₂Ru₂O₇進行磁性研究。
在本次研究裡，我們使用固態合成法燒製多晶樣品Nd₂Ru₂O₇。在Nd₂Ru₂O₇的熱容和磁化率量測中，於146、21和1.8 K處出現三個異常，分別對應於Ru⁴⁺有序、磁矩傾斜以及Nd³⁺有序。而在施加磁場後，熱容的峰值逐漸移動並變寬，這促使我們在施加磁場下進行中子粉末繞射實驗，以進一步研究其磁性結構的轉變。
Nd3+離子在50 mK時，其磁性結構為全進全出(all-in-all-out)的自旋組態。當施加磁場後，磁矩在高磁場下逐漸對齊成二進二出(two-in-two-out)的磁性結構，這讓人聯想到傳統自旋冰的自旋結構。在9 T中，Nd³⁺離子的磁矩估計為2.76(7) μB，而在400 mK的零場下，磁矩為1.54(2) μB。
μSR技術用於研究Nd₂Ru₂O₇的自旋動力學。在146 K的Ru⁴⁺有序溫度以下，可以觀察到由兩種不同的振盪頻率擬合的擺動不對稱光譜，其對應渺子所在的兩個不同的磁性位置。μSR實驗結果的相變溫度與中子和室內量測的結果一致。

Nd-pyrochlore compounds host moment fragmentation, octupolar order, and spin chirality, etc., novel phenomena. Here we report the studies on the double pyrochlore compound of Nd₂Ru₂O₇ using neutron powder diffraction, μSR techniques, and in-house heat capacity, ac susceptibility measurements.
Polycrystalline Nd₂Ru₂O₇ had been prepared for the studies. Heat capacity and magnetic susceptibility measurements on Nd₂Ru₂O₇ reveal three anomalies at 146, 21, and 1.8 K corresponding to Ru⁴⁺ ordering, moment canting, and Nd³⁺ ordering separately. The peaks of heat capacity shift and broaden in applied fields gradually motivated us to carry out neutron powder diffraction experiments in applied fields to investigate the variations of magnetic structures.
The magnetic structure of Nd³⁺ ion at 50 mK exhibits as an all-in-all-out spin configuration. When the fields were applied, the magnetic moments had been aligned gradually to a two-in-two-out magnetic structure at high field, reminiscent of spin configurations of a classical spin ice. The magnetic moment of the Nd³⁺ ion is estimated as 2.76(7) μB in 9 T, in contrast to the moment of 1.54(2) μB in zero field and 400 mK. μSR experiments had been employed to study the spin dynamics of Nd₂Ru₂O₇. Wiggling asymmetry spectra, which can be fitted by two different oscillation frequencies, were observed below the Ru⁴⁺ order temperature of 146 K, indicating two different magnetic sites where muons are located. The transition temperatures determined by μSR are consistent with the neutron and in-house measurements.

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