2015 Fiscal Year Final Research Report
Microscopic investigation of insulator-metal transitions in rare-earth compounds
| Project/Area Number |
26800193
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| Research Category |
Grant-in-Aid for Young Scientists (B)
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| Allocation Type | Multi-year Fund |
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| Research Field |
Condensed matter physics II
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| Research Institution | University of Hyogo |
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Principal Investigator |
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| Project Period (FY) |
2014-04-01 – 2016-03-31
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| Keywords | 希土類化合物 / サマリウム / 絶縁体-金属転移 / 圧力 / 核磁気共鳴 |
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| Outline of Final Research Achievements |
Pressure-induced insulator-metal transitions in SmS and SmB6 have been studied since these properties were reported in 1960’s. However, there remains several issues still unsolved probably due to lack of microscopic study under pressure. We have performed NMR measurement on these compounds to investigate the effect of pressure on the electronic state from microscopic point of view. As for SmS, we prepared the NMR active 33S enriched sample and performed the first NMR measurement of it. Notable results about SmS are as follows. (i) 4f electrons are localized at high temperatures where Sm ion was reported to have intermediate valence. (ii) a magnetic ordering was observed as a change of 33S NMR spectrum below 18 K and above 2 GPa. (iii) The magnetic ordering regime in the sample increases with pressure and decreasing temperature at the expense of the paramagnetic regime.
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| Free Research Field |
固体物理
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