diff --git a/main.tex b/main.tex index 78718754ea2f13b71b37d17717893de25c266ff7..2ef3f8ace2b17907cce77a407a28c9eb88fcc8d7 100644 --- a/main.tex +++ b/main.tex @@ -44,7 +44,7 @@ superscriptaddress, floatfix, longbibliography]{revtex4-2} \node[shape=circle,draw,inner sep=1pt] (char) {#1};}} \MakeRobustCommand\circled -\newcommand{\su}{SU} +\newcommand{\su}[1]{SU(#1)} \newcommand{\bvec}[1]{\boldsymbol #1} \newcommand{\Ucrit}{U_\mathrm{c}} @@ -301,9 +301,9 @@ presented in the following. \begin{tabular}{cccc} \toprule {$\gamma$} & Spatial & Spin & Total \\ \hline \sym A 1 & \numberedHexagon{$\Delta_s$}{1}{1}{1}{1}{1}{1} - & $d_0$ + & $\Psi$ & $\begin{gathered} - \Delta_{s} d_0 \\ + \Delta_{s} \Psi \\ \Delta_{p_x} d_x - \Delta_{p_y} d_y \end{gathered}$ \\ \sym A 2 & --- & $d_z$ @@ -339,7 +339,7 @@ presented in the following. \begin{bmatrix} \Delta_{d_{xy}} \\ \Delta_{d_{x^-y^2}} - \end{bmatrix} d_0 \\ + \end{bmatrix} \Psi \\ \Delta_f \begin{bmatrix} d_x \\ d_y @@ -360,43 +360,45 @@ presented in the following. The second column is the basis function in real space, for example, as the bond pairing on nearest neighbour bonds. The third column is the two-spin basis function, in terms of the typical superconducting psuedo- - vector formulation $d$. The fourth column is the total + vector formulation $(\Psi, \bvec d)$. The fourth column is the total spatial and two-spin basis function, calculated as decribed in the text.} \label{tab:irrep_basis_fns} \end{table} The divergent eigenstate will belong to one of the irreps of the point symmetry group of the lattice (\textit{i.e.} \sym C {6v}). -When the state is a spin singlet or \su, this can be identified by matching the -spacial symmetry behavior with one of the spacial irrep basis functions shown +When the Hamiltonian has an \su 2 spin symmetry, the point symmetry irreps +can be identified by matching the symmetry behavior of the spatial pairing with +one of the spatial irrep basis functions shown in \cref{tab:irrep_basis_fns}, second column. -If the \su symmetry is broken by the introduction of SOC, the transformation +If the \su 2 symmetry is broken by the introduction of SOC, the transformation behaviour of the spins under symmetry group operations must be considered\,\cite{kaba2019}. -Here, the total irrep can be understood only as a combination of -the spatial symmetry and the symmetry behavior of the two spins, \textit{i.e.} -the total symmetry transformation behavior. -To construct appropriate basis functions, we first consider the transformation +Here, the irrep basis functions of the total superconducting state, hereafter +referred to as the \textit{total irrep}, can be understood only as a combination of +the spatial pairing symmetry and the symmetry behavior of the two spins, +\textit{i.e.} the total symmetry transformation behavior. +To construct these basis functions, we first consider the transformation behavior of a pair of spins under \sym C {6v}. The details of this calculation can be found in \cref{app:spin_irreps}, the resulting functions are given in \cref{tab:irrep_basis_fns}, third column. -The total irreps is constructed as the tensor product of the spin-pair and -spatial irreps. +The total irreps basis function are constructed as the tensor product of the +spin-pair and spatial pairing irreps. We retain only the products that yield physical states, \textit{i.e.} those -which are antisymmetric under exchange of all quantum indices ($E_2 \otimes -E_1$ would yield spacially even spin-triplet pairing and is discarded). -Except for the case $\sym E 1 \otimes \sym E 1$, \todo{what about $E2 -\otimes E2$?} either the spacial or the spin-pair space is one-dimensional. +which are antisymmetric under exchange of all quantum indices (\sym E 2 $\otimes$ +\sym E 1 would yield spatially even spin-triplet pairing and is discarded). +Except for the case $\sym E 1 \otimes \sym E 1$, either the spacial or the +spin-pair space is one-dimensional. In those cases, multiplication of the irreps' group characters yields the total state's characters, and thus the total irrep. The $\sym E 1 \otimes \sym E 1$ case requires a further decomposition. This can be done by either forming irrep projection operators for the total -representation, as described in \cref{app:spin_irreps} \todo{Is this actually -in here?}, or by a group theory calculation exploiting the orthogonality of -the group characters \todo{source?}. +representation, in the same way as described for the spin-pair representation +described in \cref{app:spin_irreps}, or by a group theory calculation exploiting +the orthogonality of the group characters \todo{source?}. Either results in: \begin{equation} \sym E 1 \otimes \sym E 1 = \sym A 1 \oplus \sym B 2 \oplus \sym E 2 \, .