2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/23260We consider a strongly correlated "t,t'-J" spin model with a positive uniaxial anisotropy. We show that in 2+1 dimensions, this model is equivalent to spin-charge excitations coupled to Z_2 Ising gauge fields and not to a U(1) gauge fields (as in the "t-J" model). As a result a phase of frozen Z_2 gauge fluctuations is possible, giving rise to a spin-charge-separated liquid.122pages, no figuresi; improved contents (david@sci.ccny.cuny.edu)Strongly Correlated Electronstext