Table 3 Fermion bilinear and monopole symmetries on the kagome lattice

From: Unifying description of competing orders in two-dimensional quantum magnets

 

T 1

T 2

R y

C 6

\({\cal{T}}\)

M 00

+

+

+

M 01

M03

M 02

+

M 02

+

M 02

M03

+

M 03

+

M01

M01

+

M i0

+

+

+

+

M i1

Mi3

M i2

M i2

+

M i2

Mi3

M i3

+

Mi1

Mi1

\({\mathrm{\Phi }}_1^\dagger\)

\(- {\mathrm{\Phi }}_1^\dagger\)

\(- {\mathrm{\Phi }}_1^\dagger\)

\(-{{\Phi }}\) 3

\(e^{i\frac{{2\pi }}{3}}{\mathrm{\Phi }}_2^\dagger\)

\({{\Phi }}\) 1

\({\mathrm{\Phi }}_2^\dagger\)

\({\mathrm{\Phi }}_2^\dagger\)

\(- {\mathrm{\Phi }}_2^\dagger\)

\({{\Phi }}\) 2

\(- e^{i\frac{{2\pi }}{3}}{\mathrm{\Phi }}_3^\dagger\)

\({{\Phi }}\) 2

\({\mathrm{\Phi }}_3^\dagger\)

\(- {\mathrm{\Phi }}_3^\dagger\)

\({\mathrm{\Phi }}_3^\dagger\)

\(-{{\Phi }}\) 1

\(- e^{i\frac{{2\pi }}{3}}{\mathrm{\Phi }}_1^\dagger\)

\({{\Phi }}\) 3

\({\mathrm{\Phi }}_{4/5/6}^\dagger\)

\({\mathrm{\Phi }}_{4/5/6}^\dagger\)

\({\mathrm{\Phi }}_{4/5/6}^\dagger\)

\(-{{\Phi }}\) 4/5/6

\(e^{i\frac{{2\pi }}{3}}{\mathrm{\Phi }}_{4/5/6}^\dagger\)

\(-{{\Phi }}\) 4/5/6

  1. Symmetry transformation of fermion bilinears and monopoles on the kagome lattice, where \(M_{ij} \equiv \bar \psi \sigma ^i\tau ^j\psi\). Translations are marked in Fig. 1. Ry, C6 denotes reflection with respect to y-axis and six-fold rotation around center of hexagon. The six-fold rotation symmetry acting on monopoles cannot be incorporated into the vector representation of SO(6) owing to the nontrivial Berry phase, which is in line with the magnetic pattern expected on the kagome lattice