Index theorem and Majorana zero modes along a non-Abelian vortex in a color superconductor

Takanori Fujiwara, Takahiro Fukui, Muneto Nitta, Shigehiro Yasui

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Color superconductivity in high-density QCD exhibits the color-flavor-locked phase. To explore zero modes in the color-flavor-locked phase in the presence of a non-Abelian vortex with an SU(2) symmetry in the vortex core, we apply the index theorem to the Bogoliubov-de Gennes (BdG) Hamiltonian. From the calculation of the topological index, we find that triplet, doublet and singlet sectors of SU(2) have certain number of chiral Majorana zero modes in the limit of vanishing chemical potential. We also solve the BdG equation by the use of the series expansion to show that the number of zero modes and their chirality match the result of the index theorem. From particle-hole symmetry of the BdG Hamiltonian, we conclude that if and only if the index of a given sector is odd, one zero mode survives generically for a finite chemical potential. We argue that this result should hold nonperturbatively even in the high-density limit.

Original languageEnglish
Article number076002
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume84
Issue number7
DOIs
Publication statusPublished - 2011 Oct 6

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theorems
vortices
color
sectors
symmetry
series expansion
chirality
superconductivity
quantum chromodynamics

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

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Index theorem and Majorana zero modes along a non-Abelian vortex in a color superconductor. / Fujiwara, Takanori; Fukui, Takahiro; Nitta, Muneto; Yasui, Shigehiro.

In: Physical Review D - Particles, Fields, Gravitation and Cosmology, Vol. 84, No. 7, 076002, 06.10.2011.

Research output: Contribution to journalArticle

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