title: Universal and nonuniversal level statistics in a chaotic quantum spin chain.
abstract: We study the level statistics of an interacting multiqubit system, namely the kicked Ising spin chain, in the regime of quantum chaos. Long range quasienergy level statistics show effects analogous to the ones observed in semiclassical systems due to the presence of short classical periodic orbits, while short range level statistics display perfect statistical agreement with random matrix theory. Even though our system possesses no classical limit, our results suggest existence of an important nonuniversal system specific behavior at short time scale, which clearly goes beyond finite size effects in random matrix theory.
authors.affiliation: Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Mexico. carlospgmat03@gmail.com
authors.forename: Carlos
authors.initials: C
authors.lastname: Pineda
authors.forename: Tomaz
authors.initials: T
authors.lastname: Prosen