Entanglement entropy for the one-dimensional flat-band ferromagnetic Tasaki model: spontaneous symmetry breaking with one type-B Goldstone mode

Huan-Qiang Zhou, Qian-Qian Shi, Ian P. McCulloch +1

The one-dimensional flat-band ferromagnetic Tasaki model exhibits spontaneous symmetry breaking from $\mathrm{SU}(2)$ to $\mathrm{U}(1)$ with one type-B Goldstone mode, featuring that th…