Dual -1 Hahn polynomials and perfect state transfer
  We find all the $XX$ spin chains with perfect state transfer (PST) that are connected with the dual -1 Hahn polynomials $R_n(x; \alpha,\beta,N)$. For $N$ odd we recover a model that had already been identified while for $N$ even, we obtain a new system exhibiting PST. 
Luc Vinet and Alexei Zhedanov
math-ph math.CA math.MP quant-ph