Pressure dependence of superconductivity in simple-cubic Na2CsC60.
Pressure dependence of superconductivity in simple-cubic Na2CsC60.
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简单立方 Na2CsC60 中超导性的压力依赖性。
DOI：
10.1103/physrevb.50.3466
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
K. Prassides
中科院分区：
文献类型：
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作者：
Jun'ichiro Mizuki;M. Takai;H. Takahashi;N. Mori;Katsumi Tanigaki;Ichiro Hirosawa;K. Prassides
用交流磁化率方法研究了简单立方相Na 2CsC 60超导转变温度Tc与压力的关系。观测到的dTc/dP值为-12.5 ± 0.2K/GPa，明显大于先前报道的K3 C60和Rb 3C 60的dTc/dP值（分别为-7.8和-9.7K/GPa）.利用可压缩性（K3 C60），我们发现Na 2CsC 60的Tc随富勒烯间距的演化与半无序面心立方超导体M3 C60的Tc随富勒烯间距的演化有显著的不同（M=碱金属），但在良好的协议与环境压力数据的简单立方超导体Na 2 RbC 60和Na 2 CsC 60。目前的研究结果为富勒烯化物超导体的现有特征提供了一个额外的维度，确立了C 60 3−离子的相对取向在影响这些材料的电子和导电性能方面的重要性。
The pressure dependence of the superconducting transition temperature T c of simple-cubic Na 2 CsC 60 is studied by an ac susceptibility method with a Swenson-type piston-cylinder apparatus. The observed value of dT c/dP is-12.5±0.2 K/GPa, significantly larger than the values of-7.8 and-9.7 K/GPa reported earlier for K 3 C 60 and Rb 3 C 60, respectively. Using the compressibility available (that of K 3 C 60), we find that the evolution of T c with interfullerene spacing in Na 2 CsC 60 is significantly different from that established for merohedrally disordered face-centered-cubic superconductors M 3 C 60 (M= alkali metal), but in excellent agreement with the ambient pressure data for the simple cubic superconductors Na 2 RbC 60 and Na 2 CsC 60. The present results provide an additional dimension to the existing features of fulleride superconductors, establishing the importance of the relative orientation of C 60 3− ions in affecting the electronic and conducting properties of these materials.