Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material

Pal, A.; Chinotti, M.; Chu, J.-H.; Kuo, H.-H.; Fisher, I. R.; Degiorgi, L.

doi:10.1007/s10948-019-05390-4

Title: Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material

Abstract

In this work we offer a comprehensive optical investigation of the optimally hole-doped Ba_0.6K_0.4Fe₂As₂ over a broad spectral range, as a function of temperature and of tunable applied stress, which acts as an external symmetry breaking field. We show that there is a large electronic nematicity at optimal doping which extends right under the superconducting dome and implies an anisotropy of the superconducting energy gaps.

Authors:

Pal, A. ^[1]; Chinotti, M. ^[1]; Chu, J.-H. ^[2]; Kuo, H.-H. ^[2]; Fisher, I. R. ^[2]; Degiorgi, L. ^[1]

ETH Zurich (Switzerland)
Stanford Univ., CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)

Publication Date:: 2019-12-17

Research Org.:: SLAC National Accelerator Lab., Menlo Park, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR). Scientific Discovery through Advanced Computing (SciDAC); USDOE Office of Science (SC), Basic Energy Sciences (BES); Swiss National Science Foundation (SNF)

OSTI Identifier:: 1647090

Grant/Contract Number:: AC02-76SF00515

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Superconductivity and Novel Magnetism

Additional Journal Information:: Journal Volume: 33; Journal Issue: 8; Journal ID: ISSN 1557-1939

Publisher:: Springer

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Nematicity; Iron-based superconductors; Optical properties

Citation Formats


                    Pal, A., Chinotti, M., Chu, J.-H., Kuo, H.-H., Fisher, I. R., and Degiorgi, L. Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material.  United States: N. p., 2019. 
Web.  doi:10.1007/s10948-019-05390-4.

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                    Pal, A., Chinotti, M., Chu, J.-H., Kuo, H.-H., Fisher, I. R., & Degiorgi, L. Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material.  United States.  https://doi.org/10.1007/s10948-019-05390-4

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                    Pal, A., Chinotti, M., Chu, J.-H., Kuo, H.-H., Fisher, I. R., and Degiorgi, L. Tue .  
"Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material".  United States.  https://doi.org/10.1007/s10948-019-05390-4.  https://www.osti.gov/servlets/purl/1647090.

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@article{osti_1647090,

  title        = {Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material},

  author       = {Pal, A. and Chinotti, M. and Chu, J.-H. and Kuo, H.-H. and Fisher, I. R. and Degiorgi, L.},

  abstractNote = {In this work we offer a comprehensive optical investigation of the optimally hole-doped Ba0.6K0.4Fe2As2 over a broad spectral range, as a function of temperature and of tunable applied stress, which acts as an external symmetry breaking field. We show that there is a large electronic nematicity at optimal doping which extends right under the superconducting dome and implies an anisotropy of the superconducting energy gaps.},

  doi          = {10.1007/s10948-019-05390-4},

  journal      = {Journal of Superconductivity and Novel Magnetism},

  number       = 8,

  volume       = 33,

  place        = {United States},

  year         = {2019},

  month        = {12}

}

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Title: Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material

Abstract

Citation Formats

Optical conductivity of BCS superconductors with arbitrary purity journal, November 1991

Superconductivity and electronic fluctuations in Ba 1 − x K x Fe 2 As 2 studied by Raman scattering journal, February 2017

Eliashberg approach to infrared anomalies induced by the superconducting state of Ba 0.68 K 0.32 Fe 2 As 2 single crystals journal, November 2011

Colloquium : Theory of intertwined orders in high temperature superconductors journal, May 2015

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Hidden T -Linear Scattering Rate in Ba 0.6 K 0.4 Fe 2 As 2 Revealed by Optical Spectroscopy journal, September 2013

Enhancement of Superconductivity near a Nematic Quantum Critical Point journal, March 2015

Anisotropy of the In-Plane Resistivity of Underdoped Ba ( Fe 1 − x Co x ) 2 As 2 Superconductors Induced by Impurity Scattering in the Antiferromagnetic Orthorhombic Phase journal, May 2013

Effect of tensile stress on the in-plane resistivity anisotropy in BaFe 2 As 2 journal, April 2012

Cooper pairing in non-Fermi liquids journal, March 2015

Quenched disorder and vestigial nematicity in the pseudogap regime of the cuprates journal, May 2014

Effect of Co Doping on the In-Plane Anisotropy in the Optical Spectrum of Underdoped Ba ( Fe 1 − x Co x ) 2 As 2 journal, November 2012

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Discovery of orbital-selective Cooper pairing in FeSe journal, July 2017

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Optical conductivity of Ba 0.6 K 0.4 Fe 2 As 2 : The effect of in-plane and out-of-plane doping in the superconducting gap journal, November 2013

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Optical investigations of the normal and superconducting states reveal two electronic subsystems in iron pnictides journal, March 2010

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In-Plane Resistivity Anisotropy in an Underdoped Iron Arsenide Superconductor journal, August 2010

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Simultaneous Transitions in Cuprate Momentum-Space Topology and Electronic Symmetry Breaking journal, May 2014

Unprecedented anisotropic metallic state in undoped iron arsenide BaFe2As2 revealed by optical spectroscopy journal, July 2011

In-plane electronic anisotropy of underdoped ‘122’ Fe-arsenide superconductors revealed by measurements of detwinned single crystals journal, September 2011

Infrared probe of the gap evolution across the phase diagram of Ba 1 − x K x Fe 2 As 2 journal, September 2017

Optical conductivity of BCS superconductors with arbitrary purity
journal, November 1991

Superconductivity and electronic fluctuations in ${Ba}_{1 - x} K_{x} {Fe}_{2} {As}_{2}$ studied by Raman scattering
journal, February 2017

Eliashberg approach to infrared anomalies induced by the superconducting state of Ba $_{0.68}$ K $_{0.32}$ Fe $_{2}$ As $_{2}$ single crystals
journal, November 2011

Colloquium : Theory of intertwined orders in high temperature superconductors
journal, May 2015

Hysteretic behavior in the optical response of the underdoped Fe-arsenide $Ba({Fe}_{1 - x} {Co}_{x})_{2} {As}_{2}$ in the electronic nematic phase
journal, February 2014

Nematic superconducting state in iron pnictide superconductors
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Hidden $T$ -Linear Scattering Rate in ${Ba}_{0.6} K_{0.4} {Fe}_{2} {As}_{2}$ Revealed by Optical Spectroscopy
journal, September 2013

Enhancement of Superconductivity near a Nematic Quantum Critical Point
journal, March 2015

Anisotropy of the In-Plane Resistivity of Underdoped $Ba ({Fe}_{1 - x} {Co}_{x})_{2} {As}_{2}$ Superconductors Induced by Impurity Scattering in the Antiferromagnetic Orthorhombic Phase
journal, May 2013

Effect of tensile stress on the in-plane resistivity anisotropy in BaFe $_{2}$ As $_{2}$
journal, April 2012

Cooper pairing in non-Fermi liquids
journal, March 2015

Quenched disorder and vestigial nematicity in the pseudogap regime of the cuprates
journal, May 2014

Effect of Co Doping on the In-Plane Anisotropy in the Optical Spectrum of Underdoped $Ba ({Fe}_{1 - x} {Co}_{x})_{2} {As}_{2}$
journal, November 2012

Nematic-driven anisotropic electronic properties of underdoped detwinned ${Ba (Fe}_{1 - x} {Co}_{x})_{2} {As}_{2}$ revealed by optical spectroscopy
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Divergent Nematic Susceptibility in an Iron Arsenide Superconductor
journal, August 2012

Discovery of orbital-selective Cooper pairing in FeSe
journal, July 2017

Electrodynamic response in the electronic nematic phase of ${BaFe}_{2} {As}_{2}$
journal, February 2016

Optical conductivity of Ba _0.6 K _0.4 Fe ₂ As ₂ : The effect of in-plane and out-of-plane doping in the superconducting gap
journal, November 2013

Optical anisotropy in optimally doped iron-based superconductor
journal, January 2019

Measurement of the elastoresistivity coefficients of the underdoped iron arsenide Ba(Fe $_{0.975}$ Co $_{0.025}$ ) $_{2}$ As $_{2}$
journal, August 2013

Three-dimensional superconducting gap in FeSe from angle-resolved photoemission spectroscopy
journal, May 2018

Optical anisotropy in the electronic nematic phase of FeSe
journal, September 2017

Optical investigations of the normal and superconducting states reveal two electronic subsystems in iron pnictides
journal, March 2010

Nematicity at the Hund's metal crossover in iron superconductors
journal, April 2017

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journal, May 2016

Simultaneous Transitions in Cuprate Momentum-Space Topology and Electronic Symmetry Breaking
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