2004/02/29 by Ya. V. Fominov, A. A. Golubov
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.70.212513
published as A shortened version is published in Phys. Rev. B 70, 212513 (2004) · 9 pages (including 5 EPS figures), REVTeX 4
arxiv created 2004/12/30 · openalex publication_date 2004/12/30 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We consider the effect of the finite size in the ab plane on the surface density of states (DOS) in clean d-wave superconductors. We demonstrate that the angle-resolved DOS consists of energy bands that are formed similarly to the Kronig-Penney model. In contrast to the gapless DOS on a surface of a bulk sample, finiteness of the superconductor in one dimension provides the energy gap for all directions of quasiparticle motion except for \ensuremathθ=45\ifmmode^∘\else\textdegree\fi (\ensuremathθ is the angle between the trajectory and the surface normal). As a result, the angle-averaged DOS behaves linearly at low energies. At the same time, the transport DOS can still have a gap. In the special case of \ensuremathα=0\ifmmode^∘\else\textdegree\fi (\ensuremathα is the angle between the a axis of the crystal and the surface normal), the spectrum is gapped for all trajectories \ensuremathθ; the angle-averaged DOS is also gapped. For \ensuremathα=45\ifmmode^∘\else\textdegree\fi, the spectrum is gapless for all \ensuremathθ; the angle-averaged DOS is then large at low energies.