1308.1020 (A. Kumar et al.)

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

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

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.

View original: http://arxiv.org/abs/1308.1020