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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Energy barriers between metastable states in first-order quantum phase transitions

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Autor(es):
Wald, Sascha [1, 2, 3] ; Timpanaro, Andre M. [4] ; Cormick, Cecilia [5, 6] ; Landi, Gabriel T. [7]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] SISSA Int Sch Adv Studies, Via Bonomea 265, I-34136 Trieste - Italy
[2] Univ Lorraine, Lab Phys & Chim Theor, CNRS, UMR 7019, BP 239, F-54506 Vandoeuvre Les Nancy - France
[3] Univ Saarland, Theoret Phys, D-66123 Saarbrucken - Germany
[4] Univ Fed ABC, Ctr Matemat Comp & Cognicao, BR-09210580 Santo Andre - Brazil
[5] Consejo Nacl Invest Cient & Tecn, Inst Fis Enrique Gaviola, Ciudad Univ, X5016LAE, Cordoba - Argentina
[6] Univ Nacl Cordoba, Ciudad Univ, X5016LAE, Cordoba - Argentina
[7] Univ Sao Paulo, Inst Fis, BR-05314970 Sao Paulo - Brazil
Número total de Afiliações: 7
Tipo de documento: Artigo Científico
Fonte: Physical Review A; v. 97, n. 2 FEB 5 2018.
Citações Web of Science: 3
Resumo

A system of neutral atoms trapped in an optical lattice and dispersively coupled to the field of an optical cavity can realize a variation of the Bose-Hubbard model with infinite-range interactions. This model exhibits a first-order quantum phase transition between a Mott insulator and a charge density wave, with spontaneous symmetry breaking between even and odd sites, as was recently observed experimentally {[}Landig et al., Nature (London) 532, 476 (2016)]. In the present paper, we approach the analysis of this transition using a variational model which allows us to establish the notion of an energy barrier separating the two phases. Using a discrete WKB method, we then show that the local tunneling of atoms between adjacent sites lowers this energy barrier and hence facilitates the transition. Within our simplified description, we are thus able to augment the phase diagram of the model with information concerning the height of the barrier separating the metastable minima from the global minimum in each phase, which is an essential aspect for the understanding of the reconfiguration dynamics induced by a quench across a quantum critical point. (AU)

Processo FAPESP: 16/08721-7 - Modelagem estocástica de sistemas quânticos fora do equilíbrio
Beneficiário:Gabriel Teixeira Landi
Linha de fomento: Auxílio à Pesquisa - Regular