Counting solutions of the Bethe equations of the quantum group invariant open XXZ chain at roots of unity

Azat M. Gainutdinov, Wenrui Hao, Rafael I. Nepomechie +1

We consider the sl(2)_q-invariant open spin-1/2 XXZ quantum spin chain of finite length N. For the case that q is a root of unity, we propose a formula for the number of admissible…