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Title: Projective symmetry of partons in the Kitaev honeycomb model

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 91; Journal Issue: 4; Journal ID: ISSN 1098-0121
American Physical Society
Country of Publication:
United States

Citation Formats

Mellado, Paula, Petrova, Olga, and Tchernyshyov, Oleg. Projective symmetry of partons in the Kitaev honeycomb model. United States: N. p., 2015. Web. doi:10.1103/PhysRevB.91.041103.
Mellado, Paula, Petrova, Olga, & Tchernyshyov, Oleg. Projective symmetry of partons in the Kitaev honeycomb model. United States. doi:10.1103/PhysRevB.91.041103.
Mellado, Paula, Petrova, Olga, and Tchernyshyov, Oleg. 2015. "Projective symmetry of partons in the Kitaev honeycomb model". United States. doi:10.1103/PhysRevB.91.041103.
title = {Projective symmetry of partons in the Kitaev honeycomb model},
author = {Mellado, Paula and Petrova, Olga and Tchernyshyov, Oleg},
abstractNote = {},
doi = {10.1103/PhysRevB.91.041103},
journal = {Physical Review B},
number = 4,
volume = 91,
place = {United States},
year = 2015,
month = 1

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevB.91.041103

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  • Combining thermodynamic measurements with theoretical calculations we demonstrate that the iridates A{sub 2}IrO{sub 3} (A = Na, Li) are magnetically ordered Mott insulators where the magnetism of the effective spin-orbital S = 1/2 moments can be captured by a Heisenberg-Kitaev (HK) model with interactions beyond nearest-neighbor exchange. Experimentally, we observe an increase of the Curie-Weiss temperature from {Theta} {approx} -125 K for Na{sub 2}IrO{sub 3} to {Theta} {approx} -33 K for Li{sub 2}IrO{sub 3}, while the ordering temperature remains roughly the same T{sub N} {approx} 15 K. Using functional renormalization group calculations we show that this evolution of {Theta} andmore » T{sub N} as well as the low temperature zigzag magnetic order can be captured within this extended HK model. We estimate that Na{sub 2}IrO{sub 3} is deep in a magnetically ordered regime, while Li{sub 2}IrO{sub 3} appears to be close to a spin-liquid regime.« less
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  • The Kitaev honeycomb model with a topological phase transition at zero temperature is studied using the quantum-information method. Based on the exact solution of the ground state, the mutual information between two nearest sites and between two bonds with the greatest distance are obtained. It is found that the mutual information shows some singularities at the critical point where the system transits from the gapless phase to the gapped phase. Finite-size effects and scaling behavior are also studied. Our results indicate that the mutual information can serve as a good indicator of the topological phase transition. This is because themore » mutual information is believed to be able to catch some global correlation properties of the system. Meanwhile, this method has the advantages that the phase transition can be determined easily and the order parameters, which are hard to obtain for some topological phase transitions, are not necessarily known.« less
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