Raman spectroscopic evidence for superconductivity at 645 K in single-walled carbon nanotubes

Guo-meng Zhao

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Raman spectroscopic evidence for superconductivity at 645 K in single-walled carbon nanotubes

Guo-meng Zhao

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Abstract

The temperature dependent frequency shifts of the Raman active G-band have recently been measured by R.Walter et al. for single-walled carbon nanotubes containing different concentrations of the magnetic impurity Ni:Co. These Raman data can be quantitatively explained by magnetic pair-breaking effect on a superconductor with a mean-field transition temperature T_c0 of 645 K, in excellent agreement with independent electrical transport and single-particle tunneling data. We suggest that such high-T_c superconductivity might arise from the pairing interaction mediated mainly by undamped acoustic plasmons in a quasi-one-dimensional electronic system.

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Guo-meng Zhao. 2002-12-19. Raman spectroscopic evidence for superconductivity at 645 K in single-walled carbon nanotubes. https://arxiv.org/abs/cond-mat/0208200

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