su (2) symmetry of XX spin chains

Puntos clave

• The studied XX spin chain exhibits a two-fold degeneracy when a uniform transverse magnetic field is adjusted appropriately.
• Findings indicate that the system has an exact $su(2)$ symmetry with nonlocal generators determined by specific coefficients.
• The research connects the inhomogeneous spin chain behavior to discrete orthogonal polynomials, enhancing its theoretical framework.
• Understanding this symmetry could lead to advancements in quantum computing and related fields, demonstrating practical significance.