title: Probing quantum frustrated systems via factorization of the ground state.
abstract: The existence of definite orders in frustrated quantum systems is related rigorously to the occurrence of fully factorized ground states below a threshold value of the frustration. Ground-state separability thus provides a natural measure of frustration: strongly frustrated systems are those that cannot accommodate for classical-like solutions. The exact form of the factorized ground states and the critical frustration are determined for various classes of nonexactly solvable spin models with different spatial ranges of the interactions. For weak frustration, the existence of disentangling transitions determines the range of applicability of mean-field descriptions in biological and physical problems such as stochastic gene expression and the stability of long-period modulated structures.
authors.affiliation: Dipartimento di Matematica e Informatica, Università degli Studi di Salerno, CNR-SPIN, CNISM, Unità di Salerno, and INFN, Sezione di Napoli-Gruppo Collegato di Salerno, Via Ponte don Melillo, I-84084 Fisciano (SA), Italy.
authors.forename: Salvatore M
authors.initials: SM
authors.lastname: Giampaolo
authors.forename: Gerardo
authors.initials: G
authors.lastname: Adesso
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Illuminati