TY - JOUR

T1 - Quantum phase transitions in the dimerized extended Bose-Hubbard model

AU - Sugimoto, Koudai

AU - Ejima, Satoshi

AU - Lange, Florian

AU - Fehske, Holger

N1 - Funding Information:
We thank T. Yamaguchi for fruitful discussions. K.S. is grateful for the hospitality at the University of Greifswald. F.L. was supported by Deutsche Forschungsgemeinschaft (Germany) through Project No. FE 398/8-1. The iDMRG simulations were performed using the ITensor library [33] .
Publisher Copyright:
© 2019 American Physical Society.

PY - 2019/1/28

Y1 - 2019/1/28

N2 - We present an unbiased numerical density-matrix renormalization group study of the one-dimensional Bose-Hubbard model supplemented by nearest-neighbor Coulomb interaction and bond dimerization. It places the emphasis on the determination of the ground-state phase diagram and shows that, besides dimerized Mott and density-wave insulating phases, an intermediate symmetry-protected topological Haldane insulator emerges at weak Coulomb interactions for filling factor one, which disappears, however, when the dimerization becomes too large. Analyzing the critical behavior of the model, we prove that the phase boundaries of the Haldane phase to Mott insulator and density-wave states belong to the Gaussian and Ising universality classes with central charges c=1 and c=1/2, respectively, and merge in a tricritical point. Interestingly we can demonstrate a direct Ising quantum phase transition between the dimerized Mott and density-wave phases above the tricritical point. The corresponding transition line terminates at a critical end point that belongs to the universality class of the dilute Ising model with c=7/10. At even stronger Coulomb interactions the transition becomes first order.

AB - We present an unbiased numerical density-matrix renormalization group study of the one-dimensional Bose-Hubbard model supplemented by nearest-neighbor Coulomb interaction and bond dimerization. It places the emphasis on the determination of the ground-state phase diagram and shows that, besides dimerized Mott and density-wave insulating phases, an intermediate symmetry-protected topological Haldane insulator emerges at weak Coulomb interactions for filling factor one, which disappears, however, when the dimerization becomes too large. Analyzing the critical behavior of the model, we prove that the phase boundaries of the Haldane phase to Mott insulator and density-wave states belong to the Gaussian and Ising universality classes with central charges c=1 and c=1/2, respectively, and merge in a tricritical point. Interestingly we can demonstrate a direct Ising quantum phase transition between the dimerized Mott and density-wave phases above the tricritical point. The corresponding transition line terminates at a critical end point that belongs to the universality class of the dilute Ising model with c=7/10. At even stronger Coulomb interactions the transition becomes first order.

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U2 - 10.1103/PhysRevA.99.012122

DO - 10.1103/PhysRevA.99.012122

M3 - Article

AN - SCOPUS:85060683768

VL - 99

JO - Physical Review A

JF - Physical Review A

SN - 2469-9926

IS - 1

M1 - 012122

ER -