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arXiv · 2104.14152

Stripe order in the doped Hubbard model on the honeycomb lattice

Xu Yang·Hao Zheng·Mingpu Qin
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Abstract

We study the ground state properties of the doped Hubbard model with strong interactions on honeycomb lattice by the Density Matrix Renormalization Group (DMRG) method. At half-filling, due to the absence of minus sign problem, it is now well established by large-scale Quantum Monte Carlo calculations that a Dirac semi-metal to anti-ferromagnetic Mott insulator transition occurs with the increase of the interaction strength $U$ for the Hubbard model on honeycomb lattice. However, an understanding of the fate of the anti-ferromagnetic Mott insulator when holes are doped into the system is still lacking. In this work, by calculating the local spin and charge density for width-4 cylinders with DMRG, we discover a half-filled stripe order in the doped Hubbard model on honeycomb lattice. We also perform complementary large-scale mean-field calculations with renormalized interaction strength. We observe half-filled stripe order and find stripe states with filling close to one half are nearly degenerate in energy.

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Xu Yang, Hao Zheng, Mingpu Qin. 2021-04-29. Stripe order in the doped Hubbard model on the honeycomb lattice. https://doi.org/10.1103/physrevb.103.155110

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