Spin-1/2 operators exactly mapped to spinful canonical Fermi operators present in two bands

Abstract Recently, it has been shown that the quantum spin–1/2 spin operators can be exactly transformed not only in spinless, but also in spinful canonical Fermi operators in 1D [1] and 2D [2] as well. In this paper, using the same technique based on an extended Jordan–Wigner transformation, we show in 1D that the quantum spin-1/2 operators can be exactly transformed also in spinful canonical Fermi operators of spin-1/2 fermions that are belong to two bands.