Topological degeneracy and vortex manipulation in Kitaev's honeycomb model

Autor:	Kells, G., Bolukbasi, A. T., Lahtinen, V., Slingerland, J. K., Pachos, J. K., Vala, J.
Rok vydání:	2008
Předmět:	Condensed Matter - Mesoscale and Nanoscale Physics
Zdroj:	Phys.Rev.Lett.101:240404,2008
Druh dokumentu:	Working Paper
DOI:	10.1103/PhysRevLett.101.240404
Popis:	The classification of loop symmetries in Kitaev's honeycomb lattice model provides a natural framework to study the abelian topological degeneracy. We derive a perturbative low-energy effective Hamiltonian, that is valid to all orders of the expansion and for all possible toroidal configurations. Using this form we demonstrate at what order the system's topological degeneracy is lifted by finite size effects and note that in the thermodynamic limit it is robust to all orders. Further, we demonstrate that the loop symmetries themselves correspond to the creation, propagation and annihilation of fermions. Importantly, we note that these fermions, made from pairs of vortices, can be moved with no additional energy cost. Comment: 4 pages, 3 figures, Revised version, accepted to PRL
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0804.2753 Zobrazit plný text záznamu View this record from Arxiv