Magnetic End States in a Strongly Interacting OneDimensional Topological Kondo Insulator
Topological Kondo insulators are strongly correlated materials where itinerant electrons hybridize with localized spins, giving rise to a topologically nontrivial band structure. Here, we use nonperturbative bosonization and renormalizationgroup techniques to study theoretically a onedimensional topological Kondo insulator, described as a KondoHeisenberg model, where the Heisenberg spin1/2 chain is coupled to a Hubbard chain through a Kondo exchange interaction in the pwave channel (i.e., a strongly correlated version of the prototypical TammSchockley model).We derive and solve renormalizationgroup equations at twoloop order in the Kondo parameter, and find that, at half filling, the charge degrees of freedom in the Hubbard chain acquire a Mott gap, even in the case of a noninteracting conduction band (Hubbard parameter U = 0). Furthermore, at low enough temperatures, the system maps onto a spin1/2 ladder with local ferromagnetic interactions along the rungs, effectively locking the spin degrees of freedom into a spin1 chain with frozen charge degrees of freedom. This structure behaves as a spin1 Haldane chain, a prototypical interacting topological spin model, and features two magnetic spin1/2 end states for chains with open boundary conditions. In conclusion, our analysis allows us to derive an insightful connection between topological Kondo insulators in one spatial dimensionmore »
 Authors:

^{[1]};
^{[2]};
^{[3]}
 Univ. Nacional de Rosario and Instituto de Fisica Rosario, Rosario (Argentina); Univ. of Maryland, College Park, MD (United States)
 Univ. Nacional de Rosario and Instituto de Fisica Rosario, Rosario (Argentina)
 Univ. of Maryland, College Park, MD (United States); Monash Univ., Melbourne, VIC (Australia)
 Publication Date:
 Grant/Contract Number:
 SC0001911; DESC0001911
 Type:
 Published Article
 Journal Name:
 Physical Review. X
 Additional Journal Information:
 Journal Volume: 5; Journal Issue: 2; Journal ID: ISSN 21603308
 Publisher:
 American Physical Society
 Research Org:
 Univ. of Maryland, College Park, MD (United States)
 Sponsoring Org:
 USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC22)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS
 OSTI Identifier:
 1182821
 Alternate Identifier(s):
 OSTI ID: 1452836
Lobos, Alejandro M., Dobry, Ariel O., and Galitski, Victor. Magnetic End States in a Strongly Interacting OneDimensional Topological Kondo Insulator. United States: N. p.,
Web. doi:10.1103/PhysRevX.5.021017.
Lobos, Alejandro M., Dobry, Ariel O., & Galitski, Victor. Magnetic End States in a Strongly Interacting OneDimensional Topological Kondo Insulator. United States. doi:10.1103/PhysRevX.5.021017.
Lobos, Alejandro M., Dobry, Ariel O., and Galitski, Victor. 2015.
"Magnetic End States in a Strongly Interacting OneDimensional Topological Kondo Insulator". United States.
doi:10.1103/PhysRevX.5.021017.
@article{osti_1182821,
title = {Magnetic End States in a Strongly Interacting OneDimensional Topological Kondo Insulator},
author = {Lobos, Alejandro M. and Dobry, Ariel O. and Galitski, Victor},
abstractNote = {Topological Kondo insulators are strongly correlated materials where itinerant electrons hybridize with localized spins, giving rise to a topologically nontrivial band structure. Here, we use nonperturbative bosonization and renormalizationgroup techniques to study theoretically a onedimensional topological Kondo insulator, described as a KondoHeisenberg model, where the Heisenberg spin1/2 chain is coupled to a Hubbard chain through a Kondo exchange interaction in the pwave channel (i.e., a strongly correlated version of the prototypical TammSchockley model).We derive and solve renormalizationgroup equations at twoloop order in the Kondo parameter, and find that, at half filling, the charge degrees of freedom in the Hubbard chain acquire a Mott gap, even in the case of a noninteracting conduction band (Hubbard parameter U = 0). Furthermore, at low enough temperatures, the system maps onto a spin1/2 ladder with local ferromagnetic interactions along the rungs, effectively locking the spin degrees of freedom into a spin1 chain with frozen charge degrees of freedom. This structure behaves as a spin1 Haldane chain, a prototypical interacting topological spin model, and features two magnetic spin1/2 end states for chains with open boundary conditions. In conclusion, our analysis allows us to derive an insightful connection between topological Kondo insulators in one spatial dimension and the wellknown physics of the Haldane chain, showing that the ground state of the former is qualitatively different from the predictions of the naive meanfield theory.},
doi = {10.1103/PhysRevX.5.021017},
journal = {Physical Review. X},
number = 2,
volume = 5,
place = {United States},
year = {2015},
month = {5}
}
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