title: Finite-size scaling at the first-order quantum transitions of quantum Potts chains.
abstract: We investigate finite-size effects at first-order quantum transitions. For this purpose we consider the one-dimensional q-state quantum Potts chain, in particular with q=10, which undergoes a first-order transition, separating the quantum disordered and ordered phases with a discontinuity in the energy density of the ground state. In agreement with the general theory, around the transition the low-energy properties show finite-size scaling with respect to appropriate scaling variables. Their size dependence is particularly sensitive to boundary conditions, which is a specific feature of first-order quantum transitions. Finally, we also discuss the finite-size behavior of the q-state Potts model (q≥2) at the first-order transitions driven by a parallel magnetic field, occurring in the ferromagnetic phase.
authors.affiliation: Dipartimento di Fisica dell'Università di Pisa and INFN, Largo Pontecorvo 3, I-56127 Pisa, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Campostrini
authors.affiliation: Dipartimento di Fisica dell'Università di Pisa and INFN, Largo Pontecorvo 3, I-56127 Pisa, Italy.
authors.forename: Jacopo
authors.initials: J
authors.lastname: Nespolo
authors.affiliation: Dipartimento di Fisica di "Sapienza," Università di Roma and INFN, Sezione di Roma I, I-00185 Roma, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Pelissetto
authors.affiliation: Dipartimento di Fisica dell'Università di Pisa and INFN, Largo Pontecorvo 3, I-56127 Pisa, Italy.
authors.forename: Ettore
authors.initials: E
authors.lastname: Vicari