skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Topology of gap nodes in superfluid /sup 3/He:. pi. /sub 4/ homotopy group for /sup 3/He-B disclination

Journal Article · · J. Low Temp. Phys.; (United States)
DOI:https://doi.org/10.1007/BF00682148· OSTI ID:5898079

The topologically stable zeros in the energy spectrum of Fermi excitations in superfluid /sup 3/He both in uniform phases and in textures are classified. This generalizes the classification of the defects of the order parameter in real coordinate space to the classification of zeros in the gap, which are the more general defects in coherent superfluid or superconducting states both in real space and momentum k space. The zeros are described by classes of mappings of the spherical surfaces S/sup n/, embracing the (6-n-1) dimensional manifold of zeros in six-dimensional (k, r) space, into the space of the Bogolyubov-Nambu matrices, which describe the Fermi excitations. The examples of topologically nontrivial manifolds of zeros are discussed, including the closed line of zeros in five-dimensional space, which is described by the ..pi../sub 4/ homotopy groups and exists in the core of the /sup 3/He-B disclination. This object demonstrates the coupling between the real space topology of disclination and the extended space topology of zeros in the disclination core.

Research Organization:
L.D. Landau Institute for Theoretical Physics, Moscow (USSR)
OSTI ID:
5898079
Journal Information:
J. Low Temp. Phys.; (United States), Vol. 72:5-6
Country of Publication:
United States
Language:
English