Recent study has shown emergence of Majorana quasiparticles as zero energy edge states in carbon nanotubes in proximity with a superconductor by tuning the system having a helical pair by applying magnetic field [1].
In this talk, I will show that, even in the absence of magnetic fields, zero energy edge states can also emerge in the nanotubes as a combined effect of curvature-induced Dirac point shift and strong superconducting coupling between nearest-neighbor sites [2].  These edge states exist in pair, thus they are in contrast to the Majorana quasiparticles [1].

[1] M. Marganska, L. Milz, W. Izumida, C. Strunk, M. Grifoni, arXiv:1711.03616.
[2] W. Izumida, L. Milz, M. Marganska, M. Grifoni, Phys. Rev. B 96, 125414 (2017)