Intrinsic Angular Momentum and Intrinsic Magnetic Moment of Chiral Superconductor on Two-Dimensional Square Lattice

The intrinsic magnetic moment (IMM) and intrinsic angular momentum (IAM) of a chiral superconductor with p-wave symmetry on a two-dimensional square lattice are discussed on the basis of the Bogoliubov–de Gennes equation. The IMM and IAM are shown to be on the order of μBN and ħN, respectively, N being the total number of particles, without an extra factor (Tc/TF)γ (γ = 1, 2), and parallel to the pair angular momentum. They arise from the current in the surface layer with a width on the order of the coherence length ξ0, the size of Cooper pairs. However, in a single-band model, they are considerably canceled by the contribution from the Meissner surface current in a layer with the width of the penetration depth λ, making it difficult to observe them experimentally. In the case of multi-band metals with both electron-like and hole-like bands, however, considerable cancellation still occurs for the IMM but not for the IAM, making it possible to observe the IAM selectively because the effect of the Meissner ...