1.
Phys Rev Lett
; 104(23): 237203, 2010 Jun 11.
Article
in English
| MEDLINE
| ID: mdl-20867265
ABSTRACT
We study the consequences of disorder in the Kitaev honeycomb model, considering both site dilution and exchange randomness. We show that a single vacancy binds a flux and induces a local moment. This moment is polarized by an applied field h: in the gapless phase, for small h the local susceptibility diverges as χ(h)â¼ln(1/h); for a pair of nearby vacancies on the same sublattice, this even increases to χ(h)â¼1/(h[ln(1/h)](3/2)). By contrast, weak exchange randomness does not qualitatively alter the susceptibility but has its signature in the heat capacity, which in the gapless phase is power law in temperature with an exponent dependent on disorder strength.