29 citations · 119 across the 5 of their papers we have counts for
19 papers
Berezinskii-Kosterlitz-Thouless phase transitions with long-range couplings
Guido Giachetti, Nicolo Defenu, Stefano Ruffo +1
The Berezinskii-Kostelitz-Thouless (BKT) transition is the paradigmatic example of a topological phase transition without symmetry-breaking, where a quasi-ordered phase, characteri…
Self-consistent harmonic approximation with non-local couplings
Guido Giachetti, Nicolo Defenu, Stefano Ruffo +1
We derive the self-consistent harmonic approximation for the XY model with non-local interactions. The resulting equation for the variational couplings holds for any form of t…
Metastability and discrete spectrum of long-range systems
Nicolò Defenu
Long lived quasi-stationary states (QSSs) are a signature characteristic of long-range interacting systems both in the classical and in the quantum realms. Often, they emerge after…
Quantum adiabatic cycles and their breakdown
Nicolò Defenu
An analytically solvable model for quasi-static transformations across quantum critical points featuring Bosonic quasi-particle excitations is presented. The model proves that adia…
Dynamical quantum phase transition in a bosonic system with long-range interactions
Marvin Syed, Tilman Enss, Nicolò Defenu
In this paper, we investigate the dynamical quantum phase transitions appearing in the Loschmidt echo and the time-dependent order parameter of a quantum system of harmonically cou…
Interplay of spin waves and vortices in the 2D XY model at small vortex-core energy
Ilaria Maccari, Nicolò Defenu, Lara Benfatto +2
The Berezinskii-Kosterlitz-Thouless (BKT) mechanism describes universal vortex unbinding in many two-dimensional systems, including the paradigmatic XY model. However, most of thes…