Triplet Superconductivity — p-wave Pairing & d-vector

Spin-triplet superconductors have odd-parity Cooper pairs described by a d-vector. The p-wave gap Δ(k) vanishes along nodal directions. The d-vector orientation determines the spin state of pairs; a chiral p+ip state breaks time-reversal and hosts Majorana edge modes.

Pairing State

Gap Δ(k)

d-vector

Spectrum

p-wave amplitude Δ₀ 1.00 Chiral mixing η (p+iηp_y) 0.00 Chemical potential μ 0.00 d-vector polar angle θ 90°

Triplet gap function:
Δ(k) = Δ₀(k_x + iη·k_y)/k_F

d-vector: d·σ(iσ_y) defines
equal-spin or unequal pairing.

p+ip: full gap, Chern # = 1,
Majorana edge modes at ends.

Triplet Superconductor — p-wave Pairing & d-vector

Pairing State