High-energy spin fluctuation in low-Tc iron-based superconductor LaFePO0.9

Motoyuki Ishikado; Shin ichi Shamoto; Katsuaki Kodama; Ryoichi Kajimoto; Mitsutaka Nakamura; Tao Hong; Hannu Mutka

doi:10.1038/s41598-018-33878-x

High-energy spin fluctuation in low-T_c iron-based superconductor LaFePO_0.9

Motoyuki Ishikado, Shin ichi Shamoto, Katsuaki Kodama, Ryoichi Kajimoto, Mitsutaka Nakamura, Tao Hong, Hannu Mutka

Triple-Axis

Research output: Contribution to journal › Article › peer-review

4 Scopus citations

Abstract

Spin fluctuations are widely believed to play an important role in the superconducting mechanisms of unconventional high temperature superconductors. Spin fluctuations have been observed in iron-based superconductors as well. However, in some iron-based superconductors such as LaFePO_0.9, they have not been observed by inelastic neutron scattering (INS). LaFePO_0.9 is an iron-based superconductor with a low superconducting transition temperature (T_c = 5 K), where line nodes are observed in the superconducting gap function. The line-node symmetry typically originates from sign reversal of the order parameter in spin-fluctuation-mediated superconductivity. This contradiction has been a long-standing mystery of this superconductor. Herein, spin fluctuations were found at high energies such as 30–50 meV with comparable intensities to an optimally doped LaFeAs(O, F). Based on this finding, the line-node symmetry can be explained naturally as spin-fluctuation-mediated superconductivity.

Original language	English
Article number	16343
Journal	Scientific Reports
Volume	8
Issue number	1
DOIs	https://doi.org/10.1038/s41598-018-33878-x
State	Published - Dec 1 2018

Funding

The authors thank to Prof. M. Arai, Drs. Y. Inamura, S. Wakimoto, A. Iyo, H. Eisaki, F. Esaka and Mr. F. Mizuno for their helpful discussions. Magnetic susceptibility measurements were performed by using the SQUID magnetometer (MPMS,Quantum Design Inc.) at the CROSS user laboratory (B402). INS experiments at J-PARC MLF were carried out under project numbers 2009A0087, 2014A0114 and 2017I0001. The experiment at ILL was conducted under the experiment number DIR-97 as a support program (Director’s Discretion Time (DIR)) to the earthquake damage of Japanese neutron facilities. This work was supported by JST, Transformative Research-Project on Iron Pnictides (TRiP), Grant-in-Aid for Specially Promoted Research, Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan (No. 17001001), and JSPS KAKENHI Grant Number JP15K17712. A portion of this research used resources at the High Flux Isotope Reactor, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory, and was partly supported by the US-Japan Collaborative Program on Neutron Scattering.

Funders	Funder number
US-Japan
Office of Science
Oak Ridge National Laboratory
Japan Society for the Promotion of Science	15K17712, 16K05023, 16K06784
Ministry of Education, Culture, Sports, Science and Technology	17001001
Japan Science and Technology Agency

Access to Document

10.1038/s41598-018-33878-x

Cite this

@article{cc2d9bd4389f4a28aed44dde9cca8c54,

title = "High-energy spin fluctuation in low-Tc iron-based superconductor LaFePO0.9 ",

abstract = "Spin fluctuations are widely believed to play an important role in the superconducting mechanisms of unconventional high temperature superconductors. Spin fluctuations have been observed in iron-based superconductors as well. However, in some iron-based superconductors such as LaFePO0.9, they have not been observed by inelastic neutron scattering (INS). LaFePO0.9 is an iron-based superconductor with a low superconducting transition temperature (Tc = 5 K), where line nodes are observed in the superconducting gap function. The line-node symmetry typically originates from sign reversal of the order parameter in spin-fluctuation-mediated superconductivity. This contradiction has been a long-standing mystery of this superconductor. Herein, spin fluctuations were found at high energies such as 30–50 meV with comparable intensities to an optimally doped LaFeAs(O, F). Based on this finding, the line-node symmetry can be explained naturally as spin-fluctuation-mediated superconductivity.",

author = "Motoyuki Ishikado and Shamoto, {Shin ichi} and Katsuaki Kodama and Ryoichi Kajimoto and Mitsutaka Nakamura and Tao Hong and Hannu Mutka",

note = "Publisher Copyright: {\textcopyright} 2018, The Author(s).",

year = "2018",

month = dec,

day = "1",

doi = "10.1038/s41598-018-33878-x",

language = "English",

volume = "8",

journal = "Scientific Reports",

issn = "2045-2322",

publisher = "Nature Research",

number = "1",

}

TY - JOUR

T1 - High-energy spin fluctuation in low-Tc iron-based superconductor LaFePO0.9

AU - Ishikado, Motoyuki

AU - Shamoto, Shin ichi

AU - Kodama, Katsuaki

AU - Kajimoto, Ryoichi

AU - Nakamura, Mitsutaka

AU - Hong, Tao

AU - Mutka, Hannu

PY - 2018/12/1

Y1 - 2018/12/1

N2 - Spin fluctuations are widely believed to play an important role in the superconducting mechanisms of unconventional high temperature superconductors. Spin fluctuations have been observed in iron-based superconductors as well. However, in some iron-based superconductors such as LaFePO0.9, they have not been observed by inelastic neutron scattering (INS). LaFePO0.9 is an iron-based superconductor with a low superconducting transition temperature (Tc = 5 K), where line nodes are observed in the superconducting gap function. The line-node symmetry typically originates from sign reversal of the order parameter in spin-fluctuation-mediated superconductivity. This contradiction has been a long-standing mystery of this superconductor. Herein, spin fluctuations were found at high energies such as 30–50 meV with comparable intensities to an optimally doped LaFeAs(O, F). Based on this finding, the line-node symmetry can be explained naturally as spin-fluctuation-mediated superconductivity.

AB - Spin fluctuations are widely believed to play an important role in the superconducting mechanisms of unconventional high temperature superconductors. Spin fluctuations have been observed in iron-based superconductors as well. However, in some iron-based superconductors such as LaFePO0.9, they have not been observed by inelastic neutron scattering (INS). LaFePO0.9 is an iron-based superconductor with a low superconducting transition temperature (Tc = 5 K), where line nodes are observed in the superconducting gap function. The line-node symmetry typically originates from sign reversal of the order parameter in spin-fluctuation-mediated superconductivity. This contradiction has been a long-standing mystery of this superconductor. Herein, spin fluctuations were found at high energies such as 30–50 meV with comparable intensities to an optimally doped LaFeAs(O, F). Based on this finding, the line-node symmetry can be explained naturally as spin-fluctuation-mediated superconductivity.

UR - http://www.scopus.com/inward/record.url?scp=85056142463&partnerID=8YFLogxK

U2 - 10.1038/s41598-018-33878-x

DO - 10.1038/s41598-018-33878-x

M3 - Article

C2 - 30397220

AN - SCOPUS:85056142463

SN - 2045-2322

VL - 8

JO - Scientific Reports

JF - Scientific Reports

IS - 1

M1 - 16343

ER -

High-energy spin fluctuation in low-T_c iron-based superconductor LaFePO_0.9

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this