Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Spin fluctuations and superconductivity in a three-dimensional tight-binding model for BaFe2⁢As2

Journal Article · · Physical Review. B, Condensed Matter and Materials Physics
 [1];  [2];  [3];  [2];  [2];  [4]
  1. University of Augsburg (Germany)
  2. University of Florida, Gainesville, FL (United States)
  3. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
  4. University of California, Santa Barbara, CA (United States)
+ Show Author Affiliations

Despite the wealth of experimental data on the Fe-pnictide compounds of the K⁢Fe2⁢As2 type, K = Ba, Ca, or Sr, the main theoretical work based on multiorbital tight-binding models has been restricted so far to the study of the related 1111 compounds. This can be ascribed to the more three-dimensional electronic structure found by ab initio calculations for the 122 materials, making this system less amenable to model development. In addition, the more complicated Brillouin zone (BZ) of the body-centered tetragonal symmetry does not allow a straightforward unfolding of the electronic band structure into an effective 1Fe/unit cell BZ. Here we present an effective five-orbital tight-binding fit of the full density functional theory band structure for BaFe2⁢As2 including the kz dispersions. We compare the five-orbital spin fluctuation model to one previously studied for LaOFeAs and calculate the random-phase approximation enhanced susceptibility. Using the fluctuation exchange approximation to determine the leading pairing instability, we then examine the differences between a strictly two-dimensional model calculation over a single kz cut of the BZ and a completely three-dimensional approach. We find pairing states quite similar to the 1111 materials, with generic quasi-isotropic pairing on the hole sheets and nodal states on the electron sheets at kz = 0, which however are gapped as the system is hole doped. On the other hand, a substantial kz dependence of the order parameter remains, with most of the pairing strength deriving from processes near kz = π. Furthermore, these states exhibit a tendency for an enhanced anisotropy on the hole sheets and a reduced anisotropy on the electron sheets near the top of the BZ.

Research Organization:
University of Florida, Gainesville, FL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
Grant/Contract Number:
FG02-02ER45995; FG02-05ER46236
OSTI ID:
2484126
Alternate ID(s):
OSTI ID: 986789
Journal Information:
Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 21 Vol. 81; ISSN 1098-0121
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (48)

Iron-Based Layered Superconductor:  LaOFeP journal August 2006
Iron-Based Layered Superconductor La[O 1- x F x ]FeAs ( x = 0.05−0.12) with T c = 26 K journal March 2008
Unconventional superconductivity in Ba0.6K0.4Fe2As2 from inelastic neutron scattering journal December 2008
Normal-state spin dynamics and temperature-dependent spin-resonance energy in optimally doped BaFe1.85Co0.15As2 journal December 2009
Multiple Nodeless Superconducting Gaps in (Ba 0.6 K 0.4 )Fe 2 As 2 Superconductor from Angle-Resolved Photoemission Spectroscopy journal December 2008
QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials journal September 2009
Near-degeneracy of several pairing channels in multiorbital models for the Fe pnictides journal February 2009
Comparison of Monte Carlo and diagrammatic calculations for the two-dimensional Hubbard model journal February 1993
Maximally localized generalized Wannier functions for composite energy bands journal November 1997
Strong-coupling theory of superconductivity in a degenerate Hubbard model journal March 2004
Pairing symmetry in a two-orbital Hubbard model on a square lattice journal June 2007
Spin-density-wave anomaly at 140 K in the ternary iron arsenide BaFe 2 As 2 journal July 2008
Electronic structure and doping in BaFe 2 As 2 and LiFeAs: Density functional calculations journal September 2008
F 19 NMR investigation of the iron pnictide superconductor LaFeAsO 0.89 F 0.11 journal September 2008
Momentum dependence of superconducting gap, strong-coupling dispersion kink, and tightly bound Cooper pairs in the high- T c ( Sr , Ba ) 1 − x ( K , Na ) x Fe 2 As 2 superconductors journal November 2008
Momentum dependence of the superconducting gap in Ba 1 − x K x Fe 2 As 2 journal February 2009
London penetration depth in single crystals of Ba ( Fe 1 − x Co x ) 2 As 2 spanning underdoped to overdoped compositions journal March 2009
Spin gap and magnetic resonance in superconducting BaFe 1.9 Ni 0.1 As 2 journal May 2009
Pnictogen height as a possible switch between high- T c nodeless and low- T c nodal pairings in the iron-based superconductors journal June 2009
Effects of cobalt doping and three-dimensionality in BaFe 2 As 2 journal September 2009
Quasiparticle heat transport in single-crystalline Ba 1 − x K x Fe 2 As 2 : Evidence for a k -dependent superconducting gap without nodes journal October 2009
Momentum dependence and nodes of the superconducting gap in the iron pnictides journal October 2009
Functional renormalization-group study of the doping dependence of pairing symmetry in the iron pnictide superconductors journal November 2009
Band- and momentum-dependent electron dynamics in superconducting Ba ( Fe 1 − x Co x ) 2 As 2 as seen via electronic Raman scattering journal November 2009
Local antiferromagnetic correlations in the iron pnictide superconductors LaFeAsO 1 − x F x and Ca ( Fe 1 − x Co x ) 2 As 2 as seen via normal-state susceptibility journal January 2010
Evidence from anisotropic penetration depth for a three-dimensional nodal superconducting gap in single-crystalline Ba ( Fe 1 − x Ni x ) 2 As 2 journal February 2010
As 75 NMR Studies of Superconducting LaFeAs O 0.9 F 0.1 journal July 2008
Unconventional Superconductivity with a Sign Reversal in the Order Parameter of LaFeAsO 1 − x F x journal July 2008
Unconventional Pairing Originating from the Disconnected Fermi Surfaces of Superconducting LaFeAsO 1 − x F x journal August 2008
Superconductivity at 38 K in the Iron Arsenide ( Ba 1 − x K x ) Fe 2 As 2 journal September 2008
Superconductivity at 22 K in Co-Doped BaFe 2 As 2 Crystals journal September 2008
Momentum Dependence of the Superconducting Gap in NdFeAsO 0.9 F 0.1 Single Crystals Measured by Angle Resolved Photoemission Spectroscopy journal October 2008
Microwave Penetration Depth and Quasiparticle Conductivity of PrFeAsO 1 − y Single Crystals: Evidence for a Full-Gap Superconductor journal January 2009
Two-dimensional resonant magnetic excitation in BaFe 1.84 Co 0.16 As 2 journal March 2009
Inelastic Neutron-Scattering Measurements of a Three-Dimensional Spin Resonance in the FeAs-Based BaFe 1.9 Ni 0.1 As 2 Superconductor journal March 2009
Unconventional London Penetration Depth in Single-Crystal Ba ( Fe 0.93 Co 0.07 ) 2 As 2 Superconductors journal March 2009
Evidence for a Nodal-Line Superconducting State in LaFePO journal April 2009
Microwave Surface-Impedance Measurements of the Magnetic Penetration Depth in Single Crystal Ba 1 − x K x Fe 2 As 2 Superconductors: Evidence for a Disorder-Dependent Superfluid Density journal May 2009
Nonexponential London Penetration Depth of FeAs-Based Superconducting R FeAsO 0.9 F 0.1 ( R = La , Nd) Single Crystals journal June 2009
Doping Dependence of Heat Transport in the Iron-Arsenide Superconductor Ba ( Fe 1 − x Co x ) 2 As 2 : From Isotropic to a Strongly k -Dependent Gap Structure journal February 2010
Conserving Approximations for Strongly Correlated Electron Systems: Bethe-Salpeter Equation and Dynamics for the Two-Dimensional Hubbard Model journal February 1989
Evolution from Itinerant Antiferromagnet to Unconventional Superconductor with Fluorine Doping in LaFeAs(O 1- x F x ) Revealed by 75 As and 139 La Nuclear Magnetic Resonance journal July 2008
Strong-Coupling Spin-Singlet Superconductivity with Multiple Full Gaps in Hole-Doped Ba 0.6 K 0.4 Fe 2 As 2 Probed by 57 Fe-NMR journal October 2009
Comparison of Ab initio Low-Energy Models for LaFePO, LaFeAsO, BaFe 2 As 2 , LiFeAs, FeSe, and FeTe: Electron Correlation and Covalency journal April 2010
Competing orders and spin-density-wave instability in La(O 1−x F x )FeAs journal June 2008
Observation of Fermi-surface–dependent nodeless superconducting gaps in Ba 0.6 K 0.4 Fe 2 As 2 journal July 2008
Spin-singlet superconductivity with multiple gaps in PrFeAsO 0.89 F 0.11 journal July 2008
Superconducting gap symmetry of Ba 0.6 K 0.4 Fe 2 As 2 studied by angle-resolved photoemission spectroscopy journal March 2009

Similar Records

Spin fluctuations and superconductivity in a 3D tight-binding model for BaFe2As2
Journal Article · Thu Dec 31 23:00:00 EST 2009 · Physical Review. B, Condensed Matter and Materials Physics · OSTI ID:986789
Stabilization of s -wave superconductivity through arsenic p -orbital hybridization in electron-doped BaFe2As2
Journal Article · Thu Jul 12 00:00:00 EDT 2018 · Physical Review B · OSTI ID:1468135
Interdependence of spin structure, anion height and electronic structure of BaFe{sub 2}As{sub 2}
Journal Article · Fri May 06 00:00:00 EDT 2016 · AIP Conference Proceedings · OSTI ID:22591333

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY