This title appears in the Scientific Report :
2019
Please use the identifier:
http://hdl.handle.net/2128/24177 in citations.
Please use the identifier: http://dx.doi.org/10.1103/PhysRevB.100.075141 in citations.
Avoiding ergodicity problems in lattice discretizations of the Hubbard model
Avoiding ergodicity problems in lattice discretizations of the Hubbard model
The Hubbard model arises naturally when electron-electron interactions are added to the tight-binding descriptions of many condensed matter systems. For instance, the two-dimensional Hubbardmodel on the honeycomb lattice is central to the ab initio description of the electronic structure ofcarbon na...
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Personal Name(s): | Wynen, Jan-Lukas (Corresponding author) |
---|---|
Berkowitz, Evan / Körber, Christopher / Lähde, Timo A. / Luu, Tom | |
Contributing Institute: |
JARA - HPC; JARA-HPC Theorie der starken Wechselwirkung; IKP-3 Theorie der Starken Wechselwirkung; IAS-4 |
Published in: | Physical review / B, 100 (2019) 7, S. 075141 |
Imprint: |
Woodbury, NY
Inst.
2019
|
DOI: |
10.1103/PhysRevB.100.075141 |
Document Type: |
Journal Article |
Research Program: |
Carbon Nano-Structures with High-Performance Computing Theory, modelling and simulation |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://dx.doi.org/10.1103/PhysRevB.100.075141 in citations.
The Hubbard model arises naturally when electron-electron interactions are added to the tight-binding descriptions of many condensed matter systems. For instance, the two-dimensional Hubbardmodel on the honeycomb lattice is central to the ab initio description of the electronic structure ofcarbon nanomaterials, such as graphene. Such low-dimensional Hubbard models are advantageouslystudied with Markov chain Monte Carlo methods, such as Hybrid Monte Carlo (HMC). HMC is thestandard algorithm of the lattice gauge theory community, as it is well suited to theories of dynamicalfermions. As HMC performs continuous, global updates of the lattice degrees of freedom, it providessuperior scaling with system size relative to local updating methods. A potential drawback of HMCis its susceptibility to ergodicity problems due to so-called exceptional configurations, for which thefermion operator cannot be inverted. Recently, ergodicity problems were found in some formulationsof HMC simulations of the Hubbard model. Here, we address this issue directly and clarify underwhat conditions ergodicity is maintained or violated in HMC simulations of the Hubbard model.We study different lattice formulations of the fermion operator and provide explicit, representativecalculations for small systems, often comparing to exact results. We show that a fermion operatorcan be found which is both computationally convenient and free of ergodicity problems. |