Suppression of antiferromagnetic spin fluctuations in superconducting Cr0.8Ru0.2

M. Ramazanoglu; B. G. Ueland; D. K. Pratt; L. W. Harriger; J. W. Lynn; G. Ehlers; G. E. Granroth; S. L. Bud'Ko; P. C. Canfield; D. L. Schlagel; A. I. Goldman; T. A. Lograsso; R. J. McQueeney

doi:10.1103/PhysRevB.98.134512

Suppression of antiferromagnetic spin fluctuations in superconducting Cr0.8Ru0.2

M. Ramazanoglu, B. G. Ueland, D. K. Pratt, L. W. Harriger, J. W. Lynn, G. Ehlers, G. E. Granroth, S. L. Bud'Ko, P. C. Canfield, D. L. Schlagel, A. I. Goldman, T. A. Lograsso, R. J. McQueeney

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

2 Scopus citations

Abstract

Unconventional superconductivity (SC) often develops in magnetic metals on the cusp of static antiferromagnetic (AFM) order where spin fluctuations are strong. This association is so compelling that many SC materials are labeled as unconventional by proximity to an ordered AFM state. The Cr-Ru alloy system possesses such a phase diagram [see Fig. 1(a)]. Here we use inelastic neutron scattering to show that spin fluctuations are present in a SC Cr0.8Ru0.2 alloy (Tc=1.35 K). However, the neutron spin resonance, a possible signature of unconventional SC, is not observed. Instead, data indicate a spin gap of order 2Δ (the superconducting gap) and a suppression of magnetic spectral weight at energies well above 2Δ. The suppression decreases the magnetic exchange energy, suggesting that low energy spin fluctuations oppose the formation of SC. In conjunction with other experimental evidence, a possible scenario is that conventional SC sits on the cusp of AFM order in Cr-Ru alloys.

Original language	English
Article number	134512
Journal	Physical Review B
Volume	98
Issue number	13
DOIs	https://doi.org/10.1103/PhysRevB.98.134512
State	Published - Oct 25 2018

Funding

This research was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. This research was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.

Funders	Funder number
Office of Basic Energy Sciences
U.S. Department of Energy
Oak Ridge National Laboratory
Iowa State University	DE-AC02-07CH11358
Division of Materials Sciences and Engineering

Access to Document

10.1103/PhysRevB.98.134512

Cite this

Ramazanoglu, M., Ueland, B. G., Pratt, D. K., Harriger, L. W., Lynn, J. W., Ehlers, G., Granroth, G. E., Bud'Ko, S. L., Canfield, P. C., Schlagel, D. L., Goldman, A. I., Lograsso, T. A., & McQueeney, R. J. (2018). Suppression of antiferromagnetic spin fluctuations in superconducting Cr0.8Ru0.2. Physical Review B, 98(13), Article 134512. https://doi.org/10.1103/PhysRevB.98.134512

@article{4e35d3bb3f754b22bf4cc93269f1fd15,

title = "Suppression of antiferromagnetic spin fluctuations in superconducting Cr0.8Ru0.2",

abstract = "Unconventional superconductivity (SC) often develops in magnetic metals on the cusp of static antiferromagnetic (AFM) order where spin fluctuations are strong. This association is so compelling that many SC materials are labeled as unconventional by proximity to an ordered AFM state. The Cr-Ru alloy system possesses such a phase diagram [see Fig. 1(a)]. Here we use inelastic neutron scattering to show that spin fluctuations are present in a SC Cr0.8Ru0.2 alloy (Tc=1.35 K). However, the neutron spin resonance, a possible signature of unconventional SC, is not observed. Instead, data indicate a spin gap of order 2Δ (the superconducting gap) and a suppression of magnetic spectral weight at energies well above 2Δ. The suppression decreases the magnetic exchange energy, suggesting that low energy spin fluctuations oppose the formation of SC. In conjunction with other experimental evidence, a possible scenario is that conventional SC sits on the cusp of AFM order in Cr-Ru alloys.",

author = "M. Ramazanoglu and Ueland, {B. G.} and Pratt, {D. K.} and Harriger, {L. W.} and Lynn, {J. W.} and G. Ehlers and Granroth, {G. E.} and Bud'Ko, {S. L.} and Canfield, {P. C.} and Schlagel, {D. L.} and Goldman, {A. I.} and Lograsso, {T. A.} and McQueeney, {R. J.}",

note = "Publisher Copyright: {\textcopyright} 2018 American Physical Society.",

year = "2018",

month = oct,

day = "25",

doi = "10.1103/PhysRevB.98.134512",

language = "English",

volume = "98",

journal = "Physical Review B",

issn = "2469-9950",

publisher = "American Physical Society",

number = "13",

}

TY - JOUR

T1 - Suppression of antiferromagnetic spin fluctuations in superconducting Cr0.8Ru0.2

AU - Ramazanoglu, M.

AU - Ueland, B. G.

AU - Pratt, D. K.

AU - Harriger, L. W.

AU - Lynn, J. W.

AU - Ehlers, G.

AU - Granroth, G. E.

AU - Bud'Ko, S. L.

AU - Canfield, P. C.

AU - Schlagel, D. L.

AU - Goldman, A. I.

AU - Lograsso, T. A.

AU - McQueeney, R. J.

PY - 2018/10/25

Y1 - 2018/10/25

N2 - Unconventional superconductivity (SC) often develops in magnetic metals on the cusp of static antiferromagnetic (AFM) order where spin fluctuations are strong. This association is so compelling that many SC materials are labeled as unconventional by proximity to an ordered AFM state. The Cr-Ru alloy system possesses such a phase diagram [see Fig. 1(a)]. Here we use inelastic neutron scattering to show that spin fluctuations are present in a SC Cr0.8Ru0.2 alloy (Tc=1.35 K). However, the neutron spin resonance, a possible signature of unconventional SC, is not observed. Instead, data indicate a spin gap of order 2Δ (the superconducting gap) and a suppression of magnetic spectral weight at energies well above 2Δ. The suppression decreases the magnetic exchange energy, suggesting that low energy spin fluctuations oppose the formation of SC. In conjunction with other experimental evidence, a possible scenario is that conventional SC sits on the cusp of AFM order in Cr-Ru alloys.

AB - Unconventional superconductivity (SC) often develops in magnetic metals on the cusp of static antiferromagnetic (AFM) order where spin fluctuations are strong. This association is so compelling that many SC materials are labeled as unconventional by proximity to an ordered AFM state. The Cr-Ru alloy system possesses such a phase diagram [see Fig. 1(a)]. Here we use inelastic neutron scattering to show that spin fluctuations are present in a SC Cr0.8Ru0.2 alloy (Tc=1.35 K). However, the neutron spin resonance, a possible signature of unconventional SC, is not observed. Instead, data indicate a spin gap of order 2Δ (the superconducting gap) and a suppression of magnetic spectral weight at energies well above 2Δ. The suppression decreases the magnetic exchange energy, suggesting that low energy spin fluctuations oppose the formation of SC. In conjunction with other experimental evidence, a possible scenario is that conventional SC sits on the cusp of AFM order in Cr-Ru alloys.

UR - http://www.scopus.com/inward/record.url?scp=85055718903&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.98.134512

DO - 10.1103/PhysRevB.98.134512

M3 - Article

AN - SCOPUS:85055718903

SN - 2469-9950

VL - 98

JO - Physical Review B

JF - Physical Review B

IS - 13

M1 - 134512

ER -

Suppression of antiferromagnetic spin fluctuations in superconducting Cr0.8Ru0.2

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this