由於籠狀結構R5M6Sn18中因為結構的關係造成許多異常的物理特性，像是在近期R5Rh6Sn18（R = Y, Lu, Sc）系列中發現三者都屬於非一般性的超導體，且在Y5Rh6Sn18與Lu5Rh6Sn18有 time reversal symmetry breaking的現象，因而造成R5M6Sn18結構吸引了許多物理學家的關注。
在本篇論文利用錫助熔劑長晶法（Sn flux method）製成Lu5M6Sn18（M = Co, Rh, Ir）單晶，利用X光繞射（X-ray diffraction）進行結構上的分析並確認單晶的純度，接著對Lu5M6Sn18（M = Co, Rh, Ir）系列進行測量直流磁化率（DC magnetization）、電阻率（Electrical resistivity﹐ρ）、比熱（Specific heat），研究Lu5M6Sn18（M＝Co, Rh, Ir）系列樣品中的物理性質。從磁化率得到了Lu5M6Sn18（M＝Co, Rh, Ir）系列的超導臨界溫度（Tc）分別在1.3 K、4 K與3 K，從電阻中在超導臨界溫度之上可以看出Lu5Co6Sn18¬與Lu5Ir6Sn18是屬於金屬性（metallic），但是在Lu5Rh6Sn18中當溫度下降時電阻率卻是上升，因此Lu5Rh6Sn18為壞金屬（bad metal）或是半金屬（semimetal）其性質與Y5Rh6Sn18相似，接著超導態下擬合出Lu5M6Sn18（M＝Co, Rh, Ir）系列中的臨界磁場（Hc2）分別在0.5 T、5 T與2 T。在比熱的測量上，可以發現Lu5Rh6Sn18是屬於強耦合超導體（strong coupled superconductor），但是Lu5Co6Sn18與Lu5Ir6Sn18是屬於弱耦合超導體（weakly coupled superconductors）。

Some of the interesting phenomenon, like unusual superconductivity and time reversal symmetry breaking in family of caged compounds R5M6Sn18 (R = rare earth, M = transition metal) has motivated researchers around the world to work on these materials. We have investigated the caged compounds Lu5M6Sn18 (M = Co, Rh, Ir) to study their low temperature properties using dc magnetization, specific heat and resistivity measurement techniques. We have prepared single crystals of Lu5M6Sn18 (M = Co, Rh, Ir) materials by using Sn-flux method. All three compounds show superconducting behavior below Tc ≈ 1.2 K (Co), 4 K (Rh) and 2.9 K (Ir). The heat capacity measurements reveal Lu5Rh6Sn18 is a strongly coupled superconductor, while Lu5M6Sn18 (M = Co, Ir) are weakly coupled superconductors. Resistivity measurements reveal that Lu5Co6Sn18, Lu5Ir6Sn18 show metallic behavior above Tc, however, Lu5Rh6Sn18 is characterized as a bad metal as its resistivity decreases with the increase in the temperature. The all three compounds are observed to show s-wave superconductivity with isotropic superconducting gap.

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