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arXiv · 1308.1020

Temperature dependence of Andreev spectra in a superconducting carbon nanotube quantum dot

A. Kumar·M. Gaim·D. Steininger·A. Levy Yeyati·A. Martin-Rodero·A. K. Huettel·C. Strunk
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Abstract

Tunneling spectroscopy of a Nb coupled carbon nanotube quantum dot reveals the formation of pairs of Andreev bound states (ABS) within the superconducting gap. A weak replica of the lower ABS is found, which is generated by quasi-particle tunnelling from the ABS to the Al tunnel probe. An inversion of the ABS-dispersion is observed at elevated temperatures, which signals the thermal occupation of the upper ABS. Our experimental findings are well supported by model calculations based on the superconducting Anderson model.

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A. Kumar, M. Gaim, D. Steininger, A. Levy Yeyati, A. Martin-Rodero, A. K. Huettel, C. Strunk. 2013-12-21. Temperature dependence of Andreev spectra in a superconducting carbon nanotube quantum dot. https://doi.org/10.1103/physrevb.89.075428

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