RT Journal Article T1 Supersymmetric spin chains with nonmonotonic dispersion relation: criticality and entanglement entropy A1 Carrasco, José A. A1 Finkel Morgenstern, Federico A1 González López, Artemio A1 Rodríguez, Miguel A. AB We study the critical behavior and the ground-state entanglement of a large class of su(1|1) supersymmetric spin chains with a general (not necessarily monotonic) dispersion relation. We show that this class includes several relevant models, with both short-and long-range interactions of a simple form. We determine the low temperature behavior of the free energy per spin, and deduce that the models considered have a critical phase in the same universality class as a (1 + 1)-dimensional conformal field theory (CFT) with central charge equal to the number of connected components of the Fermi sea. We also study the Renyi entanglement entropy of the ground state, deriving its asymptotic behavior as the block size tends to infinity. In particular, we show that this entropy exhibits the logarithmic growth characteristic of (1 + 1)-dimensional CFTs and one-dimensional (fermionic) critical lattice models, with a central charge consistent with the low-temperature behavior of the free energy. Our results confirm the widely believed conjecture that the critical behavior of fermionic lattice models is completely determined by the topology of their Fermi surface. PB American Physical Society SN 2470-0045 YR 2017 FD 2017-01-17 LK https://hdl.handle.net/20.500.14352/17691 UL https://hdl.handle.net/20.500.14352/17691 LA eng NO ©2017 American Physical Society.The authors would like to thank P. Tempesta for several enlightening discussions. This work was partially supported by Spain’s MINECO under Research Grant No. FIS2015-63966- P. J.A.C. would also like to acknowledge the financial support of the Universidad Complutense de Madrid through a 2015 predoctoral scholarship. NO Ministerio de Economía y Competitividad (MINECO) NO Universidad Complutense de Madrid DS Docta Complutense RD 4 abr 2025