The Berezinskii-Kosterlitz-Thouless (BKT) transition is the paradigmatic example of a topological phase transition without symmetry breaking, where a quasiordered phase, characterized by a power-law scaling of the correlation functions at low temperature, is disrupted by the proliferation of topological excitations above the critical temperature TBKT. In this Letter, we consider the effect of long-range decaying couplings ∼r-2-σ on the BKT transition. After pointing out the relevance of this nontrivial problem, we discuss the phase diagram, which is far richer than the corresponding short-range one. It features - for 7/4<2 - a quasiordered phase in a finite temperature range TcTBKT. The transition temperature Tc displays unique universal features quite different from those of the traditional, short-range XY model. Given the universal nature of our findings, they may be observed in current experimental realizations in 2D atomic, molecular, and optical quantum systems.
Berezinskii-Kosterlitz-Thouless Phase Transitions with Long-Range Couplings / Giachetti, G.; Defenu, N.; Ruffo, S.; Trombettoni, A.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 127:15(2021), pp. 1-7. [10.1103/PhysRevLett.127.156801]
Berezinskii-Kosterlitz-Thouless Phase Transitions with Long-Range Couplings
Giachetti, G.;Defenu, N.;Ruffo, S.
;Trombettoni, A.
2021-01-01
Abstract
The Berezinskii-Kosterlitz-Thouless (BKT) transition is the paradigmatic example of a topological phase transition without symmetry breaking, where a quasiordered phase, characterized by a power-law scaling of the correlation functions at low temperature, is disrupted by the proliferation of topological excitations above the critical temperature TBKT. In this Letter, we consider the effect of long-range decaying couplings ∼r-2-σ on the BKT transition. After pointing out the relevance of this nontrivial problem, we discuss the phase diagram, which is far richer than the corresponding short-range one. It features - for 7/4<2 - a quasiordered phase in a finite temperature range TcTBKT. The transition temperature Tc displays unique universal features quite different from those of the traditional, short-range XY model. Given the universal nature of our findings, they may be observed in current experimental realizations in 2D atomic, molecular, and optical quantum systems.File | Dimensione | Formato | |
---|---|---|---|
2104.13217.pdf
accesso aperto
Descrizione: file pdf depositato su arxiv
Tipologia:
Documento in Pre-print
Licenza:
Non specificato
Dimensione
597 kB
Formato
Adobe PDF
|
597 kB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.