= Spin-triplet p-wave pairing
{title2=$S=1,\ L=1$}
<Spin-triplet p-wave pairing> has pair <spin> $S=1$ and orbital <angular momentum> $L=1$, allowing multiple <order parameters> beyond conventional <BCS theory> with zero orbital <angular momentum>. <The Extraordinary Phases of Liquid 3He by David Morris Lee>[Lee, 1996 lecture; 1997 reprint p.658]{ref}
Specifying this symmetry does not determine its microscopic attraction mechanism. A short exchange-symmetry check explains why these quantum numbers fit <fermions>. The <spin-one-half triplet states> $|\uparrow\uparrow\rangle$, $(|\uparrow\downarrow\rangle+|\downarrow\uparrow\rangle)/\sqrt2$ and $|\downarrow\downarrow\rangle$ are symmetric under exchange. A stipulated orbital factor proportional to relative <momentum> $k_x$ changes sign under $\mathbf k\mapsto-\mathbf k$. Multiplying any symmetric <spin> function by that odd orbital factor gives an antisymmetric pair <wave function>, as required by <Fermi-Dirac statistics>. By comparison, an even s-wave orbital factor needs the antisymmetric <spin singlet state>. This checks compatibility with exchange statistics; it neither selects a stable phase nor derives its transition <temperature>.
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