Correspondence between Andreev reflection and Klein tunneling in bipolar graphene
Abstract
Andreev reflection at a superconductor and Klein tunneling through an n-p junction in graphene are two processes that couple electrons to holes -- the former through the superconducting pair potential Delta and the latter through the electrostatic potential U. We derive that the energy spectra in the two systems are identical, at low energies E<<Delta and for an antisymmetric potential profile U(-x,y)=-U(x,y). This correspondence implies that bipolar junctions in graphene may have zero density of states at the Fermi level and carry a current in equilibrium, analogously to superconducting Josephson junctions. It also implies that nonelectronic systems with the same band structure as graphene, such as honeycomb-lattice photonic crystals, can exhibit pseudo-superconducting behavior.
Cite
@article{arxiv.0710.1309,
title = {Correspondence between Andreev reflection and Klein tunneling in bipolar graphene},
author = {C. W. J. Beenakker and A. R. Akhmerov and P. Recher and J. Tworzydlo},
journal= {arXiv preprint arXiv:0710.1309},
year = {2013}
}
Comments
7 pages, 7 figures; much expanded version, with a revised title, test of the analytics by computer simulation, temperature dependence of the persistent current, and an appendix with details of the calculation