Quasiparticle interference and symmetry of superconducting order parameter in strongly electron-doped iron-based superconductors

Böker, Jakob; Volkov, Pavel A.; Hirschfeld, P. J.; Eremin, Ilya

doi:10.1088/1367-2630/ab2a82

Title: Quasiparticle interference and symmetry of superconducting order parameter in strongly electron-doped iron-based superconductors

Abstract

Motivated by recent experimental reports of significant spin–orbit coupling (SOC) and a signchanging order-parameter in the Li_1-xFe_x(OHFe)_1-yZn_ySe superconductor with only electron pockets present, we study the possible Cooper-pairing symmetries and their quasiparticle interference (QPI) signatures.Wefind that each of the resulting states—s-wave, d-wave and helical p-wave—can have a fully gapped density of states consistent with angle-resolved photoemission spectroscopy experiments and, due to SOC, are a mixture of spin singlet and triplet components leading to intraand inter-band features in the QPI signal. Analyzing predicted QPI patterns we find that only the spintriplet dominated even parity A _1g (s-wave) and B _2g (d-wave) pairing states are consistent with the experimental data. Additionally, we show that these states can indeed be realized in a microscopic model with atomic-like interactions and study their possible signatures in spin-resolved STM experiments.

Authors:: Böker, Jakob; Volkov, Pavel A.; Hirschfeld, P. J.; Eremin, Ilya

Publication Date:: Thu Aug 01 00:00:00 EDT 2019

Research Org.:: Univ. of Florida, Gainesville, FL (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; Russian Federation

OSTI Identifier:: 1549199

Alternate Identifier(s):: OSTI ID: 1603845

Grant/Contract Number:: FG02-05ER46236; ER 463/8-1; N57316180; K2-2017-085

Resource Type:: Published Article

Journal Name:: New Journal of Physics

Additional Journal Information:: Journal Name: New Journal of Physics Journal Volume: 21 Journal Issue: 8; Journal ID: ISSN 1367-2630

Publisher:: IOP Publishing

Country of Publication:: United Kingdom

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; unconventional superconductivity; iron-based systems; scanning tunneling spectroscopy; superconducting order parameter; spin–orbit coupling; phase sensitive probes

Citation Formats


                    Böker, Jakob, Volkov, Pavel A., Hirschfeld, P. J., and Eremin, Ilya. Quasiparticle interference and symmetry of superconducting order parameter in strongly electron-doped iron-based superconductors.  United Kingdom: N. p., 2019. 
Web.  doi:10.1088/1367-2630/ab2a82.

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                    Böker, Jakob, Volkov, Pavel A., Hirschfeld, P. J., & Eremin, Ilya. Quasiparticle interference and symmetry of superconducting order parameter in strongly electron-doped iron-based superconductors.  United Kingdom.  https://doi.org/10.1088/1367-2630/ab2a82

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                    Böker, Jakob, Volkov, Pavel A., Hirschfeld, P. J., and Eremin, Ilya. Thu .  
"Quasiparticle interference and symmetry of superconducting order parameter in strongly electron-doped iron-based superconductors".  United Kingdom.  https://doi.org/10.1088/1367-2630/ab2a82.

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@article{osti_1549199,

  title        = {Quasiparticle interference and symmetry of superconducting order parameter in strongly electron-doped iron-based superconductors},

  author       = {Böker, Jakob and Volkov, Pavel A. and Hirschfeld, P. J. and Eremin, Ilya},

  abstractNote = {Motivated by recent experimental reports of significant spin–orbit coupling (SOC) and a signchanging order-parameter in the Li1-xFex(OHFe)1-yZnySe superconductor with only electron pockets present, we study the possible Cooper-pairing symmetries and their quasiparticle interference (QPI) signatures.Wefind that each of the resulting states—s-wave, d-wave and helical p-wave—can have a fully gapped density of states consistent with angle-resolved photoemission spectroscopy experiments and, due to SOC, are a mixture of spin singlet and triplet components leading to intraand inter-band features in the QPI signal. Analyzing predicted QPI patterns we find that only the spintriplet dominated even parity A 1g (s-wave) and B 2g (d-wave) pairing states are consistent with the experimental data. Additionally, we show that these states can indeed be realized in a microscopic model with atomic-like interactions and study their possible signatures in spin-resolved STM experiments.},

  doi          = {10.1088/1367-2630/ab2a82},

  journal      = {New Journal of Physics},

  number       = 8,

  volume       = 21,

  place        = {United Kingdom},

  year         = {Thu Aug 01 00:00:00 EDT 2019},

  month        = {Thu Aug 01 00:00:00 EDT 2019}

}

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Title: Quasiparticle interference and symmetry of superconducting order parameter in strongly electron-doped iron-based superconductors

Abstract

Citation Formats

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