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Gate-controlled superconductivity in diffusive multiwalled carbon nanotube

T. Tsuneta·L. Lechner·P. J. Hakonen
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Abstract

We have investigated electrical transport in a diffusive multiwalled carbon nanotube contacted using superconducting leads made of Al/Ti sandwich structure. We find proximity-induced superconductivity with measured critical currents up to I_cm = 1.3 nA, tunable by gate voltage down to 10 pA. The supercurrent branch displays a finite zero bias resistance which varies as R_0 proportional to I_cm^-alpha with alpha=0.74. Using IV-characteristics of junctions with phase diffusion, a good agreement is obtained with Josephson coupling energy in the long, diffusive junction model of A.D Zaikin and G.F. Zharkov (Sov. J. Low Temp. Phys. 7, 184 (1981)).

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T. Tsuneta, L. Lechner, P. J. Hakonen. 2006-08-22. Gate-controlled superconductivity in diffusive multiwalled carbon nanotube. https://doi.org/10.1103/physrevlett.98.087002

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