Kondo impurities in the Kitaev spin liquid: Numerical renormalization group solution and gauge-flux-driven screening

التفاصيل البيبلوغرافية
العنوان: Kondo impurities in the Kitaev spin liquid: Numerical renormalization group solution and gauge-flux-driven screening
المؤلفون: Vojta, Matthias, Mitchell, Andrew K., Zschocke, Fabian
المصدر: Phys. Rev. Lett. 117, 037202 (2016)
سنة النشر: 2016
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Statistical Mechanics
الوصف: Kitaev's honeycomb-lattice compass model describes a spin liquid with emergent fractionalized excitations. Here we study the physics of isolated magnetic impurities coupled to the Kitaev spin-liquid host. We reformulate this Kondo-type problem in terms of a many-state quantum impurity coupled to a multichannel bath of Majorana fermions and present the numerically exact solution using Wilson's numerical renormalization group technique. Quantum phase transitions occur as a function of Kondo coupling and locally applied field. At zero field, the impurity moment is partially screened only when it binds an emergent gauge flux, and otherwise becomes free at low temperatures. We show how Majorana degrees of freedom determine the fixed-point properties, make contact with Kondo screening in pseudogap Fermi systems, and discuss effects away from the dilute limit.
Comment: 5+10 pages, 5+9 figs, (v2) minor modifications, final version as published
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevLett.117.037202
URL الوصول: http://arxiv.org/abs/1604.03557
رقم الأكسشن: edsarx.1604.03557
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevLett.117.037202