Magic in the spectra of the XXZ quantum chain with boundaries at Delta=0 and Delta=-1/2

Jan de Gier, Alexander Nichols, Pavel Pyatov +1

We show that from the spectra of the U_q (sl(2)) symmetric XXZ spin-1/2 finite quantum chain at Delta=-1/2 (q=e^{pi i/3}) one can obtain the spectra of certain XXZ quantum chains w…