https://doi.org/10.1140/epjb/e2006-00028-x
A conformal field theory description of magnetic flux fractionalization in Josephson junction ladders*
1
Dipartimento di Scienze Fisiche, Universitá di Napoli “Federico II” and INFN, Sezione di Napoli, Via Cintia, Compl. universitario M.
Sant'Angelo, 80126 Napoli, Italy
2
Dipartimento di Scienze Fisiche, Universitá di Napoli “Federico II” and Coherentia-INFM, Unità di Napoli, Via Cintia, Compl. universitario M. Sant'Angelo, 80126 Napoli, Italy
3
Sissa and INFN, Sezione di Trieste, Via Beirut 1, 34100 Trieste, Italy
Corresponding author: a adele.naddeo@na.infn.it
Received:
30
September
2005
Revised:
15
December
2005
Published online:
31
January
2006
We show how the recently proposed effective theory for a Quantum Hall system
at “paired states” filling 
[1,2], the twisted model (TM), well adapts to describe the
phenomenology of Josephson Junction ladders (JJL) in the presence of defects. In particular it is shown how naturally the phenomenon of flux fractionalization takes place in such a description and its relation with the discrete symmetries present in the TM. Furthermore we focus on
“closed” geometries, which enable us to analyze the topological properties of the ground state of the system in relation to the presence of half flux quanta.
PACS: 11.25.Hf – Conformal field theory, algebraic structures / 02.20.Sv – Lie algebras of Lie groups / 03.65.Fd – Algebraic methods
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2006
