Yuan-Yao He

TL;DR: In this paper, a comparative study of state-of-the-art quantum many-body methods is performed using the half-filled Hubbard model at weak coupling as testing grounds, with two numerically exact methods (diagrammatic and determinantal quantum Monte Carlo) serving as a benchmark.

Abstract: The authors thank Chong Wang and Meng Cheng for helpful discussions. Y. Q. Q., Y,-Y.H., Z.-Y.L., and Z. Y. M. are supported by the Ministry of Science and Technology of China under Grant No. 2016YFA0300502, the National Science Foundation of China under Grants No. 91421304, No. 11421092, No. 11474356, No. 11574359, and No. 11674370, and the National Thousand-Young-Talents Program of China. Y. Q. Q. would like to thank Boston University for support under its Condensed Matter Theory Visitors Program. Y.-Y. H. acknowledges the Cultivation of Outstanding Innovative Talents Program 2016 of Renmin University of China. The work of A. S. is partly supported through the Partner Group program between the Indian Association for the Cultivation of Science (Kolkata) and the Max Planck Institute for the Physics of Complex Systems (Dresden). A. W. S. is supported by the NSF under Grant No. DMR-1410126 and would also like to thank the Institute of Physics, Chinese Academy of Sciences for visitor support. C. X. is supported by the David and Lucile Packard Foundation and NSF Grant No. DMR-1151208. We thank the following institutions for allocation of CPU time: the Center for Quantum Simulation Sciences in the Institute of Physics, Chinese Academy of Sciences, the Physical Laboratory of High Performance Computing in the Renmin University of China, the Tianhe-1A platform at the National Supercomputer Center in Tianjin, and the Tianhe-2 platform at the National Supercomputer Center in Guangzhou. (2016YFA0300502 - Ministry of Science and Technology of China; 91421304 - National Science Foundation of China; 11421092 - National Science Foundation of China; 11474356 - National Science Foundation of China; 11574359 - National Science Foundation of China; 11674370 - National Science Foundation of China; National Thousand-Young-Talents Program of China; Boston University; Indian Association for the Cultivation of Science (Kolkata); Max Planck Institute for the Physics of Complex Systems (Dresden); DMR-1410126 - NSF; DMR-1151208 - NSF; David and Lucile Packard Foundation)

TL;DR: In this paper, the sign problem in standard determinantal quantum Monte Carlo (DQMC) using a gauge constraint in auxiliary-field space is solved using a self-consistent procedure coupling the many-body computation with an independent particle calculation.

TL;DR: In this article, the Kane-Mele-Hubbard model was applied to an AA-stacking bilayer honeycomb lattice with interlayer antiferromagnetic interaction, and a bona fide topological phase transition between the spin and charge gap of the system closed while the single-particle excitations remained gapped.

TL;DR: In this paper, a multiloop extension of the functional renormalization group (fRG) flow equations for the self-energy and two-particle vertex allows for a precise match with the parquet approximation also for two-dimensional lattice problems.