DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Anomalous scaling of Δ C versus T c in the Fe-based superconductors: the $${S}_{\pm }$$-wave pairing state model

Abstract

The strong power law behavior of the specific heat jump $${\rm{\Delta }}C\;$$ versus T c $$({\rm{\Delta }}C/{T}_{{\rm{c}}}\sim {T}_{{\rm{c}}}^{\alpha },\alpha \approx 2)$$, first observed by Bud'ko et al (2009 Phys. Rev. B 79 220516), has been confirmed with several families of the Fe-based superconducting compounds with various dopings. We tested a minimal two band BCS model to understand this anomalous behavior and showed that this non-BCS relation between $${\rm{\Delta }}C\;$$ versus T c is a generic property of the multiband superconducting state paired by a dominant interband interaction ($${V}_{\mathrm{inter}}\gt {V}_{\mathrm{intra}}$$) reflecting the relation $$\frac{{{\rm{\Delta }}}_{{\rm{h}}}}{{{\rm{\Delta }}}_{{\rm{e}}}}\sim \sqrt{\frac{{N}_{{\rm{e}}}}{{N}_{{\rm{h}}}}}$$ near T c, as in the $${S}_{\pm }$$-wave pairing state. We also found that this $${\rm{\Delta }}C\;$$ versus T c power law can continuously change from the ideal BNC scaling to a considerable deviation by a moderate variation of the impurity scattering rate $${{\rm{\Gamma }}}_{0}$$ (non-pair-breaking). Finally, as a result, our model provides a consistent explanation why the electron-doped Fe-based superconductors follow the ideal BNC scaling very well while the hole-doped systems often show varying degree of deviations.

Authors:
;
Publication Date:
Research Org.:
Univ. of Florida, Gainesville, FL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1236522
Alternate Identifier(s):
OSTI ID: 1236523; OSTI ID: 1254478
Grant/Contract Number:  
FG02-86ER45268; 2013-R1A1A2-057535
Resource Type:
Published Article
Journal Name:
New Journal of Physics
Additional Journal Information:
Journal Name: New Journal of Physics Journal Volume: 18 Journal Issue: 2; Journal ID: ISSN 1367-2630
Publisher:
IOP Publishing
Country of Publication:
United Kingdom
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Fe-based superconductors; specific heat jump versus Tc,BNC scailing, S±-pairing state, two band model

Citation Formats

Bang, Yunkyu, and Stewart, G. R. Anomalous scaling of Δ C versus T c in the Fe-based superconductors: the ${S}_{\pm }$-wave pairing state model. United Kingdom: N. p., 2016. Web. doi:10.1088/1367-2630/18/2/023017.
Bang, Yunkyu, & Stewart, G. R. Anomalous scaling of Δ C versus T c in the Fe-based superconductors: the ${S}_{\pm }$-wave pairing state model. United Kingdom. https://doi.org/10.1088/1367-2630/18/2/023017
Bang, Yunkyu, and Stewart, G. R. Mon . "Anomalous scaling of Δ C versus T c in the Fe-based superconductors: the ${S}_{\pm }$-wave pairing state model". United Kingdom. https://doi.org/10.1088/1367-2630/18/2/023017.
@article{osti_1236522,
title = {Anomalous scaling of Δ C versus T c in the Fe-based superconductors: the ${S}_{\pm }$-wave pairing state model},
author = {Bang, Yunkyu and Stewart, G. R.},
abstractNote = {The strong power law behavior of the specific heat jump ${\rm{\Delta }}C\;$ versus T c $({\rm{\Delta }}C/{T}_{{\rm{c}}}\sim {T}_{{\rm{c}}}^{\alpha },\alpha \approx 2)$, first observed by Bud'ko et al (2009 Phys. Rev. B 79 220516), has been confirmed with several families of the Fe-based superconducting compounds with various dopings. We tested a minimal two band BCS model to understand this anomalous behavior and showed that this non-BCS relation between ${\rm{\Delta }}C\;$ versus T c is a generic property of the multiband superconducting state paired by a dominant interband interaction (${V}_{\mathrm{inter}}\gt {V}_{\mathrm{intra}}$) reflecting the relation $\frac{{{\rm{\Delta }}}_{{\rm{h}}}}{{{\rm{\Delta }}}_{{\rm{e}}}}\sim \sqrt{\frac{{N}_{{\rm{e}}}}{{N}_{{\rm{h}}}}}$ near T c, as in the ${S}_{\pm }$-wave pairing state. We also found that this ${\rm{\Delta }}C\;$ versus T c power law can continuously change from the ideal BNC scaling to a considerable deviation by a moderate variation of the impurity scattering rate ${{\rm{\Gamma }}}_{0}$ (non-pair-breaking). Finally, as a result, our model provides a consistent explanation why the electron-doped Fe-based superconductors follow the ideal BNC scaling very well while the hole-doped systems often show varying degree of deviations.},
doi = {10.1088/1367-2630/18/2/023017},
journal = {New Journal of Physics},
number = 2,
volume = 18,
place = {United Kingdom},
year = {Mon Feb 01 00:00:00 EST 2016},
month = {Mon Feb 01 00:00:00 EST 2016}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
https://doi.org/10.1088/1367-2630/18/2/023017

Citation Metrics:
Cited by: 5 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Effect of spin-density wave fluctuations on the specific heat jump in iron pnictides at the superconducting transition
journal, April 2014


Doping-dependent specific heat study of the superconducting gap in Ba ( Fe 1 x Co x ) 2 As 2
journal, May 2010


Superconducting specific-heat jump Δ C el T c β ( β 2 ) for K 1 x Na x Fe 2 As 2
journal, February 2014


Doping evolution of superconducting gaps and electronic densities of states in Ba(Fe 1−x Co x ) 2 As 2 iron pnictides
journal, August 2010


Selective Mott Physics as a Key to Iron Superconductors
journal, April 2014


Multigap superconductivity in single crystals of Ba 0.65 Na 0.35 Fe 2 As 2 : A calorimetric investigation
journal, August 2011


Pair breaking in iron pnictides
journal, December 2009


Unconventional Superconductivity with a Sign Reversal in the Order Parameter of LaFeAsO 1 x F x
journal, July 2008


Properties of Superconducting Alloys Containing Paramagnetic Impurities
journal, December 1964


Gap structure in the electron-doped iron–arsenide superconductor Ba(Fe 0.92 Co 0.08 ) 2 As 2 : low-temperature specific heat study
journal, February 2010


Calorimetric evidence of multiband superconductivity in Ba ( Fe 0.925 Co 0.075 ) 2 As 2 single crystals
journal, February 2010


Band Structure of the Heavily-Electron-Doped FeAs-Based Ba ( Fe , Co ) 2 As 2 Superconductor Suppresses Antiferromagnetic Correlations
journal, April 2010


Quasiparticle Mass Enhancement Close to the Quantum Critical Point in BaFe 2 ( As 1 x P x ) 2
journal, June 2013


Unconventional Pairing Originating from the Disconnected Fermi Surfaces of Superconducting LaFeAsO 1 x F x
journal, August 2008


Band Structure and Fermi Surface of an Extremely Overdoped Iron-Based Superconductor KFe 2 As 2
journal, July 2009


Specific heat and angle-resolved photoemission spectroscopy study of the superconducting gaps in LiFeAs
journal, June 2011


Strong pairbreaking in anisotropic superconductors
journal, May 2010


Possible Multiple Gap Superconductivity with Line Nodes in Heavily Hole-Doped Superconductor KFe 2 As 2 Studied by 75 As Nuclear Quadrupole Resonance and Specific Heat
journal, August 2009

  • Fukazawa, Hideto; Yamada, Yuji; Kondo, Kenji
  • Journal of the Physical Society of Japan, Vol. 78, Issue 8
  • DOI: 10.1143/JPSJ.78.083712

Heat capacity jump at T c and pressure derivatives of superconducting transition temperature in the Ba 1 x Na x Fe 2 As 2 ( 0.1 x 0.9 ) series
journal, January 2014


Coexistence of isotropic and extended s -wave order parameters in FeSe as revealed by low-temperature specific heat
journal, December 2011


Effect of annealing on the specific heat of Ba(Fe 1 x Co x ) 2 As 2
journal, February 2011


Low temperature specific heat of the hole-doped Ba 0.6 K 0.4 Fe 2 As 2 single crystals
journal, May 2009


Magnetic and superconducting transitions in Ba 1 x K x Fe 2 As 2 studied by specific heat
journal, January 2010


Specific-heat discontinuity Δ C vs. T c in annealed Ba(Fe 1 x Co x ) 2 As 2
journal, August 2012


Phase diagram of iron pnictides if doping acts as a source of disorder
journal, December 2011


Jump in specific heat in the presence of a spin-density wave at the superconducting transition in iron pnictides
journal, October 2011


Superconducting gap symmetry of Ba 0.6 K 0.4 Fe 2 As 2 studied by angle-resolved photoemission spectroscopy
journal, March 2009


Specific Heat Measurements of Ba 0.68 K 0.32 Fe 2 As 2 Single Crystals: Evidence for a Multiband Strong-Coupling Superconducting State
journal, July 2010


Doping dependence of the specific heat of single-crystal BaFe 2 (As 1 x P x ) 2
journal, May 2012


Possible pairing states of the Fe-based superconductors
journal, October 2008


Impurity effects on the ± s -wave state of the iron-based superconductors
journal, February 2009


Calorimetric evidence of strong-coupling multiband superconductivity in Fe(Te 0 . 57 Se 0 . 43 ) single crystal
journal, April 2011