Unpaired Majorana modes on dislocations and string defects in Kitaev's honeycomb model

被引：40

作者：

Petrova, Olga ^{[1
]}

Mellado, Paula ^{[2
]}

Tchernyshyov, Oleg ^{[3
]}

机构：

[1] Max Planck Inst Phys Komplexer Syst, D-01187 Dresden, Germany

[2] Adolfo Ibanez Univ, Sch Engn & Appl Sci, Santiago, Chile

[3] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA

来源：

PHYSICAL REVIEW B | 2014年 / 90卷 / 13期

基金：

美国国家科学基金会;

关键词：

QUANTUM; ANYONS;

D O I：

10.1103/PhysRevB.90.134404

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We study the gapped phase of Kitaev's honeycomb model (a Z(2) spin liquid) on a lattice with topological defects. We find that some dislocations and string defects carry unpaired Majorana fermions. Physical excitations associated with these defects are (complex) fermion modes made out of two (real) Majorana fermions connected by a Z(2) gauge string. The quantum state of these modes is robust against local noise and can be changed by winding a Z(2) vortex around one of the dislocations. The exact solution respects gauge invariance and reveals a crucial role of the gauge field in the physics of Majorana modes. To facilitate these theoretical developments, we recast the degenerate perturbation theory for spins in the language of Majorana fermions.

引用

页数：14

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