Entropies and IPR as Markers for a Phase Transition in a Two-Level Model for Atom–Diatomic Molecule Coexistence
Baena, Ignacio
Pérez Fernández, Pedro
Rodríguez Gallardo, Manuela
Arias, José Miguel
Quantum phase transitions
Exactly solvable models
Inverse participation ratio
Rényi entropy
This work is part of the I+D+i projects PID2019-104002GB-C22 and PID2020-114687GB-I00 funded by MCIN/AEI/10.13039/501100011033. This work is also part of grant Group FQM-160, EU FEDER funds US-1380840 and the project PAIDI 2020 with reference P20_01247, funded by the Consejería de Economía, Conocimiento, Empresas y Universidad, Junta de Andalucía (Spain) and “ERDF—A Way of Making Europe”.
A quantum phase transition (QPT) in a simple model that describes the coexistence of atoms
and diatomic molecules is studied. The model, which is briefly discussed, presents a second-order
ground state phase transition in the thermodynamic (or large particle number) limit, changing from a
molecular condensate in one phase to an equilibrium of diatomic molecules–atoms in coexistence
in the other one. The usual markers for this phase transition are the ground state energy and the
expected value of the number of atoms (alternatively, the number of molecules) in the ground state.
In this work, other markers for the QPT, such as the inverse participation ratio (IPR), and particularly,
the Rényi entropy, are analyzed and proposed as QPT markers. Both magnitudes present abrupt
changes at the critical point of the QPT.
2022-02-10T12:20:03Z
2022-02-10T12:20:03Z
2022-01-12
info:eu-repo/semantics/article
Baena, I.; Pérez-Fernández, P.; Rodríguez-Gallardo, M.; Arias, J.M. Entropies and IPR as Markers for a Phase Transition in a Two-Level Model for Atom–Diatomic Molecule Coexistence. Entropy 2022, 24, 113. [https://doi.org/10.3390/e24010113]
http://hdl.handle.net/10481/72786
10.3390/e24010113
eng
http://creativecommons.org/licenses/by/3.0/es/
info:eu-repo/semantics/openAccess
Atribución 3.0 España
MDPI