A method to systematically construct the XX quantum spin chains with nearest-neighbor
interactions that allow perfect state transfer (PST) is shown. Sets of orthogonal polynomials …

We study solvable spin chains, one-dimensional massless Dirac fermions and conformal
field theories (CFTs) with sine-square deformation (SSD), in which the Hamiltonian density …

A systematic study of fractional revival at two sites in XX quantum spin chains is presented.
Analytic models with this phenomenon are obtained by combining two basic ways of …

We study the sine-square deformed quantum XY chain with open boundary conditions in
which the interaction strength at the position x in the chain of length L is proportional to the …

We give an explicit solution of aq-Riemann–Hilbert problem that arises in the theory of
orthogonal polynomials, prove that it is unique and deduce several properties. In particular …

The occurrence of fractional revival in quantum spin chains is examined. Analytic models
where this phenomenon can be exhibited in exact solutions are provided. It is explained that …

The analytic specifications of photonic lattices with fractional revival (FR) and perfect state
transfer (PST) are reviewed. The approach to their design which is based on orthogonal …

We study a linear spin chain which was originally introduced by Shi et al.[Phys. Rev. A 71
(2005), 032309, 5 pages], for which the coupling strength contains a parameter α and …

New bispectral orthogonal polynomials are obtained from an unconventional truncation of
the Askey–Wilson polynomials. In the limit q→ 1, they reduce to the para-Racah polynomials …

It is shown how choices based on the q-Racah polynomials for the masses and spring
constants along a chain give new systems that exactly allow dispersionless end-to-end …