Fractional Solitons in Excitonic Josephson Junctions.
Sci Rep
; 5: 15796, 2015 10 29.
Article
em En
| MEDLINE
| ID: mdl-26511770
ABSTRACT
The Josephson effect is especially appealing to physicists because it reveals macroscopically the quantum order and phase. In excitonic bilayers the effect is even subtler due to the counterflow of supercurrent as well as the tunneling between layers (interlayer tunneling). Here we study, in a quantum Hall bilayer, the excitonic Josephson junction a conjunct of two exciton condensates with a relative phase Ï0 applied. The system is mapped into a pseudospin ferromagnet then described numerically by the Landau-Lifshitz-Gilbert equation. In the presence of interlayer tunneling, we identify a family of fractional sine-Gordon solitons which resemble the static fractional Josephson vortices in the extended superconducting Josephson junctions. Each fractional soliton carries a topological charge Q that is not necessarily a half/full integer but can vary continuously. The calculated current-phase relation (CPR) shows that solitons with Q = Ï0/2π is the lowest energy state starting from zero Ï0 - until Ï0 > π - then the alternative group of solitons with Q = Ï0/2π - 1 takes place and switches the polarity of CPR.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article