近年來有大量的研究深入探討銥燒綠石化合物(iridated-pyrochlore)其獨特的物理現象，因其具備5d電子軌域而產生電子與電子關聯和自旋軌道耦合交互作用，在本文中我們利用固態合成法燒製樣品Tb2Ir2O7並探討多項實驗結果顯示的物理性質，從電阻、磁化率與µSR量測中驗證其在132K特有的導體絕緣體相變(metal-insulator transition)，並且同時在磁化率與µSR實驗同時觀察到在50 K和6 K的磁相變符合Tb-Ir與Tb-Tb交互作用造成的磁排列變化。歸納各項實驗數據得出Tb3+在50 K下受長程有序排列的Ir4+影響，在低溫下也形成反鐵磁性全進全出(all-in-all-out)形式的磁結構。我們在比熱數據中新發現0.1 K處出現明顯尖峰，且此訊號符合肖特基(Schottky)效應，進一步分析此比熱來源為Tb3+原子核內部的電磁場所產生的超精細結構所造成。從低溫下Tb3+磁性貢獻熵的計算上得到數值接近於Rln4，並藉由非彈性中子散射實驗確認Tb3+在基態和第一激發態為二重態。我們提出可能的交互作用力建構此系統的自旋波(spin wave)模型，並且驗證Tb3+強烈的最近鄰交互作用貢獻造成反鐵磁性全進全出有序排列磁結構。

In recent years, iridated-pyrochlore compounds with 5d-electron elements have attracted a lot of interest primarily because of the electron-electron correlations and spin-orbit interactions in these materials. We have prepared polycrystalline samples of pyrochlore Tb2Ir2O7 using conventional solid state reaction and we will present results from XRD, resistivity, magnetization, specific heat, µSR and neutron scattering experiments. Three anomalies at T ~ 132 K, 50 K and 6 K have been observed in our DC magnetization measurements. Our magnetization and resistivity measurements on Tb2Ir2O7 confirm that Ir4+ ions are ordered and undergo a metal-insulator transition (MIT) at TMI ~132 K. The muon spin relaxation (μSR) results reveal internal static field below the metal-insulator transition temperature (TMI), and three anomalies in the μSR oscillation frequencies observed near 130 K, 50 K and 6 K are consistent with the results of DC magnetization. The magnetic structure of Tb2Ir2O7 below 50 K is an antiferromagnetic "all-in-all-out" (AIAO) state. The new observed sharp peak revealed at ~0.1 K in specific heat is in line with the form of the Schottky specific heat of the Tb3+ nuclear hyperfine. The time-of-flight inelastic neutron scattering results and spin wave calculation confirm the integrated magnetic entropy approaches to the value of Rln4, indicating a doublet-doublet scheme for Tb3+ in the system. We propose the spin wave excitation model from a candidate exchange interactions, we found the strong nearest-neighbor antiferromagnetism AIAO ordered by Tb3+ sublattice.

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