We show that, by an appropriate choice of auxiliary fields and exact integration of the phonon degrees of freedom, it is possible to define a "sign-free" path integral for the so-called Hubbard-Holstein model at half filling. We use a statistical method, based on an accelerated and efficient Langevin dynamics, for evaluating all relevant correlation functions of the model. Preliminary calculations at U/t=4 and U/t=1, for ω0/t=1, indicate a region around U≃g2ω0 without either antiferromagnetic or charge-density-wave orders that is much wider compared to previous approximate calculations. The elimination of the sign problem in a model without explicit particle-hole symmetry may open different perspectives for strongly correlated models, even away from the purely attractive or particle-hole symmetric cases.

Solution of the sign problem for the half-filled Hubbard-Holstein model / Karakuzu, Seher; Seki, Kazuhiro; Sorella, Sandro. - In: PHYSICAL REVIEW. B. - ISSN 2469-9950. - 98:20(2018), pp. 1-5. [10.1103/PhysRevB.98.201108]

Solution of the sign problem for the half-filled Hubbard-Holstein model

Karakuzu, Seher
Membro del Collaboration group
;
Seki, Kazuhiro
Membro del Collaboration group
;
Sorella, Sandro
Membro del Collaboration group
2018

Abstract

We show that, by an appropriate choice of auxiliary fields and exact integration of the phonon degrees of freedom, it is possible to define a "sign-free" path integral for the so-called Hubbard-Holstein model at half filling. We use a statistical method, based on an accelerated and efficient Langevin dynamics, for evaluating all relevant correlation functions of the model. Preliminary calculations at U/t=4 and U/t=1, for ω0/t=1, indicate a region around U≃g2ω0 without either antiferromagnetic or charge-density-wave orders that is much wider compared to previous approximate calculations. The elimination of the sign problem in a model without explicit particle-hole symmetry may open different perspectives for strongly correlated models, even away from the purely attractive or particle-hole symmetric cases.
98
20
1
5
201108
http://harvest.aps.org/bagit/articles/10.1103/PhysRevB.98.201108/apsxml
https://arxiv.org/abs/1808.07759
Karakuzu, Seher; Seki, Kazuhiro; Sorella, Sandro
File in questo prodotto:
File Dimensione Formato  
HolsteinHub_sign.pdf

non disponibili

Descrizione: article
Tipologia: Versione Editoriale (PDF)
Licenza: Non specificato
Dimensione 359.77 kB
Formato Adobe PDF
359.77 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11767/87967
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 18
  • ???jsp.display-item.citation.isi??? 18
social impact