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Title: Validity of the local approximation in iron pnictides and chalcogenides

Abstract

We introduce a methodology to treat different degrees of freedom at different levels of approximation. We use cluster DMFT (dynamical mean field theory) for the t 2g electrons and single site DMFT for the e g electrons to study the normal state of the iron pnictides and chalcogenides. Furthermore, in the regime of moderate mass renormalizations, the self-energy is very local, justifying the success of single site DMFT for these materials and for other Hunds metals. Here we solve the corresponding impurity model with CTQMC (continuous time quantum Monte Carlo) and find that the minus sign problem is not severe in regimes of moderate mass renormalization.

Authors:
 [1];  [2];  [3]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States). Computational Science Initiative; Rutgers Univ., Piscataway, NJ (United States). Dept. of Physics and Astronomy
  2. Rutgers Univ., Piscataway, NJ (United States). Dept. of Physics and Astronomy
  3. Rutgers Univ., Piscataway, NJ (United States). Dept. of Physics and Astronomy; Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Dept.
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Advanced Scientific Computing Research (SC-21); USDOE
OSTI Identifier:
1392251
Alternate Identifier(s):
OSTI ID: 1355959
Report Number(s):
BNL-114281-2017-JA
Journal ID: ISSN 2469-9950; PRBMDO; TRN: US1702831
Grant/Contract Number:
SC0012704; FG02-99ER45761; DMR1405303; AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 95; Journal Issue: 19; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Sémon, Patrick, Haule, Kristjan, and Kotliar, Gabriel. Validity of the local approximation in iron pnictides and chalcogenides. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.95.195115.
Sémon, Patrick, Haule, Kristjan, & Kotliar, Gabriel. Validity of the local approximation in iron pnictides and chalcogenides. United States. doi:10.1103/PhysRevB.95.195115.
Sémon, Patrick, Haule, Kristjan, and Kotliar, Gabriel. Mon . "Validity of the local approximation in iron pnictides and chalcogenides". United States. doi:10.1103/PhysRevB.95.195115. https://www.osti.gov/servlets/purl/1392251.
@article{osti_1392251,
title = {Validity of the local approximation in iron pnictides and chalcogenides},
author = {Sémon, Patrick and Haule, Kristjan and Kotliar, Gabriel},
abstractNote = {We introduce a methodology to treat different degrees of freedom at different levels of approximation. We use cluster DMFT (dynamical mean field theory) for the t 2g electrons and single site DMFT for the e g electrons to study the normal state of the iron pnictides and chalcogenides. Furthermore, in the regime of moderate mass renormalizations, the self-energy is very local, justifying the success of single site DMFT for these materials and for other Hunds metals. Here we solve the corresponding impurity model with CTQMC (continuous time quantum Monte Carlo) and find that the minus sign problem is not severe in regimes of moderate mass renormalization.},
doi = {10.1103/PhysRevB.95.195115},
journal = {Physical Review B},
number = 19,
volume = 95,
place = {United States},
year = {Mon May 08 00:00:00 EDT 2017},
month = {Mon May 08 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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