Crossover Phase Diagram in Heavy Fermion Compound YbCo_2Zn_<20>
Crossover Phase Diagram in Heavy Fermion Compound YbCo_2Zn_<20>
复制标题
重费米子化合物 YbCo_2Zn_<20> 的交叉相图
DOI：
10.1143/jpsjs.80sa.sa052
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
et al
中科院分区：
文献类型：
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作者：
T.Takeuchi;Y.Onuki;et al
通过测量重费米子化合物YbCo_2Zn_20在磁场下的比热、交流磁化率和电阻率，研究了该化合物的电子态和变磁行为. 在10 K以下，磁比热（Cmag/T）随温度的降低而急剧增加，在0.2 K以下，磁比热为8 J/（K2·mol），表明在该温度范围内，磁比热为费米液体性质。 磁熵在10 K以下迅速增加，在60 K附近达到Rln 8，表明晶体电场（CEF）分裂能很小。 由精确的电阻率测量，结合C（H）/T和χac（T）的测量，发现在低温下H_（10）的H-T相图中存在两条交叉线<100>。 费米液体状态在比这些交叉线更低的温度下演化。
We studied the electronic state and metamagnetic behavior in the heavy fermion compound YbCo2Zn20by measuring the specific heat, ac-susceptibility, and electrical resistivity under magnetic fields. The magnetic specific heat in the form ofCmag/Tincreases steeply with decreasing temperature below 10 K and becomes constant with an extremely large value 8 J/(K2·mol) below about 0.2 K, indicating a Fermi-liquid nature in this temperature range. The magnetic entropy increases rapidly below 10 K and reachesRln 8 around 60 K, suggesting a small crystalline-electric-field (CEF) splitting energy. From the precise electrical resistivity measurements, together with theC(H)/Tand χac(T) measurements, it was found that there are two crossover lines at low temperatures in theH–Tphase diagram forH∥<100>. The Fermi-liquid state evolves at lower temperatures than these crossover lines.