Superconducting diamagnetic fluctuations in ropes of carbon nanotubes
Superconducting diamagnetic fluctuations in ropes of carbon nanotubes
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DOI：
10.1103/physrevb.73.094520
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发表时间：
2006-03-01
影响因子：
3.7
通讯作者：
Bouchiat, H
中科院分区：
文献类型：
--
作者：
Ferrier, M;Ladieu, F;Bouchiat, H
我们报告了大量的单壁碳纳米管的纯化绳低温磁化测量。尽管由于样品中仍然存在小的铁磁催化颗粒而产生超顺磁贡献，但在低温（T <0.5K）和低磁场（H < 80 Oe）下，可检测到幅度等于总磁化强度信号的1/3的抗磁信号。这种低温抗磁性可以解释为碳纳米管绳中的迈斯纳效应，这些碳纳米管先前已被证明具有超导性[M. Kociak，A. Y. Kasumov，S. Gueron，B.阿夫莱特岛I.霍多斯岛B。戈尔巴托夫科尔科夫湖Vaccarini和H. Bouchiat，Phys. Rev. Lett. 86，2416（2001）]。其振幅对应于10（-3）量级的场驱逐，并且与考虑管间约瑟夫森耦合的简单期望一致。
We report low-temperature magnetization measurements on a large number of purified ropes of single wall carbon nanotubes. In spite of a superparamagnetic contribution due to the small ferromagnetic catalytical particles still present in the sample, at low temperature (T < 0.5 K) and low magnetic field (H < 80 Oe), a diamagnetic signal is detectable with an amplitude equal to 1/3 of the total magnetization signal. This low-temperature diamagnetism can be interpreted as the Meissner effect in ropes of carbon nanotubes which have previously been shown to exhibit superconductivity from transport measurements [M. Kociak, A. Y. Kasumov, S. Gueron, B. Reulet, I. I. Khodos, Y. B. Gorbatov, V. T. Kolkov, L. Vaccarini, and H. Bouchiat, Phys. Rev. Lett. 86, 2416 (2001)]. Its amplitude corresponds to a field expulsion of the order 10(-3) and is in agreement with simple expectations taking into account the intertube Josephson coupling.