Is a color superconductor topological?

Journal Article · Thu Apr 01 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.074004· OSTI ID:21409467

Nishida, Yusuke ^[1]

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1. Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

A fully gapped state of matter, whether insulator or superconductor, can be asked if it is topologically trivial or nontrivial. Here we investigate topological properties of superconducting Dirac fermions in 3D having a color superconductor as an application. In the chiral limit, when the pairing gap is parity even, the right-handed and left-handed sectors of the free space Hamiltonian have nontrivial topological charges with opposite signs. Accordingly, a vortex line in the superconductor supports localized gapless right-handed and left-handed fermions with the dispersion relations E={+-}vp{sub z} (v is a parameter dependent velocity) and thus propagating in opposite directions along the vortex line. However, the presence of the fermion mass immediately opens up a mass gap for such localized fermions and the dispersion relations become E={+-}v{radical}(m{sup 2}+p{sub z}{sup 2}). When the pairing gap is parity odd, the situation is qualitatively different. The right-handed and left-handed sectors of the free space Hamiltonian in the chiral limit have nontrivial topological charges with the same sign and therefore the presence of the small fermion mass does not open up a mass gap for the fermions localized around the vortex line. When the fermion mass is increased further, there is a topological phase transition at m={radical}({mu}{sup 2}+{Delta}{sup 2}) and the localized gapless fermions disappear. We also elucidate the existence of gapless surface fermions localized at a boundary when two phases with different topological charges are connected. A part of our results is relevant to the color superconductivity of quarks.

• OSTI ID: 21409467
• Journal Information: Physical Review. D, Particles Fields, Vol. 81, Issue 7; Other Information: DOI: 10.1103/PhysRevD.81.074004; (c) 2010 The American Physical Society; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CHIRALITY
COLOR MODEL
DISPERSION RELATIONS
HAMILTONIANS
MASS
PARITY
PHASE TRANSFORMATIONS
QUANTUM FIELD THEORY
QUARKS
SPACE
SUPERCONDUCTIVITY
SUPERCONDUCTORS
SURFACES
TOPOLOGY
VELOCITY
VORTICES
COMPOSITE MODELS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
FERMIONS
FIELD THEORIES
MATHEMATICAL MODELS
MATHEMATICAL OPERATORS
MATHEMATICS
PARTICLE MODELS
PARTICLE PROPERTIES
PHYSICAL PROPERTIES
QUANTUM OPERATORS
QUARK MODEL