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

Title: Probing chiral superconductivity in Sr 2 RuO 4 underneath the surface by point contact measurements

Abstract

Sr2RuO4 (SRO) is the prime candidate for a chiral p-wave superconductor with critical temperature $${T}_{{\rm{c}}}(\mathrm{SRO})\sim 1.5$$ K. Chiral domains with opposite chiralities $${p}_{x}\pm {{\rm{i}}{p}}_{y}$$ have been proposed, but are yet to be confirmed. We measure the field dependence of the point contact (PC) resistance between a tungsten tip and an SRO–Ru eutectic crystal, where micrometer-sized Ru inclusions are embedded in SRO with an atomically sharp interface. Ruthenium is an s-wave superconductor with $${T}_{{\rm{c}}}(\mathrm{Ru})\sim 0.5$$ K; flux pinned near the Ru inclusions can suppress its superconductivity, as reflected in the PC resistance and spectra. This flux pinning effect originates from SRO underneath the surface and is very strong once flux is introduced. To fully remove flux pinning, one needs to thermally cycle the sample above Tc(SRO) or apply alternating fields with decreasing amplitude. With alternating fields, the observed hysteresis in magnetoresistance can be explained by domain dynamics, providing support for the existence of chiral domains. The origin of the strong pinning could be the chiral domains themselves.

Authors:
; ; ; ; ; ; ORCiD logo
Publication Date:
Research Org.:
Tulane Univ., New Orleans, LA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1437703
Alternate Identifier(s):
OSTI ID: 1393550
Grant/Contract Number:  
FG02-04ER46159; SC0012432
Resource Type:
Published Article
Journal Name:
New Journal of Physics
Additional Journal Information:
Journal Name: New Journal of Physics Journal Volume: 19 Journal Issue: 5; Journal ID: ISSN 1367-2630
Publisher:
IOP Publishing
Country of Publication:
United Kingdom
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Wang, He, Luo, Jiawei, Lou, Weijian, Ortmann, J. E., Mao, Z. Q., Liu, Y., and Wei, Jian. Probing chiral superconductivity in Sr 2 RuO 4 underneath the surface by point contact measurements. United Kingdom: N. p., 2017. Web. doi:10.1088/1367-2630/aa65c5.
Wang, He, Luo, Jiawei, Lou, Weijian, Ortmann, J. E., Mao, Z. Q., Liu, Y., & Wei, Jian. Probing chiral superconductivity in Sr 2 RuO 4 underneath the surface by point contact measurements. United Kingdom. https://doi.org/10.1088/1367-2630/aa65c5
Wang, He, Luo, Jiawei, Lou, Weijian, Ortmann, J. E., Mao, Z. Q., Liu, Y., and Wei, Jian. Mon . "Probing chiral superconductivity in Sr 2 RuO 4 underneath the surface by point contact measurements". United Kingdom. https://doi.org/10.1088/1367-2630/aa65c5.
@article{osti_1437703,
title = {Probing chiral superconductivity in Sr 2 RuO 4 underneath the surface by point contact measurements},
author = {Wang, He and Luo, Jiawei and Lou, Weijian and Ortmann, J. E. and Mao, Z. Q. and Liu, Y. and Wei, Jian},
abstractNote = {Sr2RuO4 (SRO) is the prime candidate for a chiral p-wave superconductor with critical temperature ${T}_{{\rm{c}}}(\mathrm{SRO})\sim 1.5$ K. Chiral domains with opposite chiralities ${p}_{x}\pm {{\rm{i}}{p}}_{y}$ have been proposed, but are yet to be confirmed. We measure the field dependence of the point contact (PC) resistance between a tungsten tip and an SRO–Ru eutectic crystal, where micrometer-sized Ru inclusions are embedded in SRO with an atomically sharp interface. Ruthenium is an s-wave superconductor with ${T}_{{\rm{c}}}(\mathrm{Ru})\sim 0.5$ K; flux pinned near the Ru inclusions can suppress its superconductivity, as reflected in the PC resistance and spectra. This flux pinning effect originates from SRO underneath the surface and is very strong once flux is introduced. To fully remove flux pinning, one needs to thermally cycle the sample above Tc(SRO) or apply alternating fields with decreasing amplitude. With alternating fields, the observed hysteresis in magnetoresistance can be explained by domain dynamics, providing support for the existence of chiral domains. The origin of the strong pinning could be the chiral domains themselves.},
doi = {10.1088/1367-2630/aa65c5},
journal = {New Journal of Physics},
number = 5,
volume = 19,
place = {United Kingdom},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
https://doi.org/10.1088/1367-2630/aa65c5

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

Save / Share:

Works referenced in this record:

Higher- T c superconducting phase in Sr 2 RuO 4 induced by uniaxial pressure
journal, May 2010


Lattices of double-quanta vortices and chirality inversion in p x + i p y superconductors
journal, September 2016


Critical Magnetic Fields of Superconducting Ruthenium Isotopes and Search for an Isotope Effect
journal, January 1966


Unconventional superconductivity in Sr2RuO4
journal, July 2015


Spin-Triplet Superconductivity in Sr 2 RuO 4 Probed by Andreev Reflection
journal, February 2000


Search for spontaneous edge currents and vortex imaging in Sr 2 Ru O 4 mesostructures
journal, April 2014


Magnetization process in a chiral p -wave superconductor with multidomains
journal, May 2005


Edge States of Sr 2 RuO 4 Detected by In-Plane Tunneling Spectroscopy
journal, August 2011


Anomalous switching in Nb/Ru/Sr2RuO4 topological junctions by chiral domain wall motion
journal, August 2013

  • Anwar, M. S.; Nakamura, Taketomo; Yonezawa, S.
  • Scientific Reports, Vol. 3, Issue 1
  • DOI: 10.1038/srep02480

Strong Increase of Tc of Sr2RuO4 Under Both Tensile and Compressive Strain
journal, April 2014


Search for spontaneous magnetization in Sr2RuO4
journal, May 2003


Tunneling spectroscopy of topological superconductors
journal, January 2014

  • Kashiwaya, Satoshi; Kashiwaya, Hiromi; Saitoh, Kohta
  • Physica E: Low-dimensional Systems and Nanostructures, Vol. 55
  • DOI: 10.1016/j.physe.2013.07.016

Enhanced spin-triplet superconductivity near dislocations in Sr2RuO4
journal, November 2013

  • Ying, Y. A.; Staley, N. E.; Xin, Y.
  • Nature Communications, Vol. 4, Issue 1
  • DOI: 10.1038/ncomms3596

High Resolution Polar Kerr Effect Measurements of Sr 2 RuO 4 : Evidence for Broken Time-Reversal Symmetry in the Superconducting State
journal, October 2006


Transition into a low temperature superconducting phase of unconventional pinning in Sr2RuO4
journal, January 1999


Semi-Meissner state and neither type-I nor type-II superconductivity in multicomponent superconductors
journal, November 2005


Temperature and junction-type dependency of Andreev reflection in MgB2
journal, December 2002


Tunneling and point-contact spectroscopy on NbSe2
journal, May 2000


The Role of Domain Walls on the Vortex Creep Dynamics in Unconventional Superconductors
journal, November 1999

  • Sigrist, M.; Agterberg, D. F.
  • Progress of Theoretical Physics, Vol. 102, Issue 5
  • DOI: 10.1143/PTP.102.965

Limits on superconductivity-related magnetization in Sr 2 RuO 4 and PrOs 4 Sb 12 from scanning SQUID microscopy
journal, June 2010


Topological competition of superconductivity in Pb/Ru/Sr 2 RuO 4 junctions
journal, August 2011


Type-1.5 Superconductivity
journal, March 2009


Upper limit on spontaneous supercurrents in Sr 2 Ru O 4
journal, July 2007


Scaling behavior of point contacts between a tungsten tip and the heavy-fermion superconductors
journal, October 1996

  • Gloos, K.; Anders, F. B.; Buschinger, B.
  • Journal of Low Temperature Physics, Vol. 105, Issue 1-2
  • DOI: 10.1007/BF00754627

Vortex coalescence and type-1.5 superconductivity in Sr 2 RuO 4
journal, August 2012


Vortex overlapping in a BCS type-II superconductor revealed by Andreev reflection spectroscopy
journal, April 2006


Suppression of spontaneous currents in Sr 2 RuO 4 by surface disorder
journal, October 2014


Unconventional strong pinning in multiphase superconductors
journal, May 2000


The Transition Between Real and Complex Superconducting Order Parameter Phases in UPt3
journal, June 2010


Vortex imaging and vortex lattice transitions in superconducting Sr 2 RuO 4 single crystals
journal, September 2011


Direct observation of the superconducting gap of Sr 2 RuO 4
journal, June 2002


Magnetic Behavior of Type-II Superconductors with Small Ginzburg-Landau Parameters
journal, January 1973


Enhanced superconductivity at the interface of W / Sr 2 RuO 4 point contacts
journal, May 2015


Interface superconductivity in the eutectic Sr 2 RuO 4 Ru : 3-K phase of Sr 2 RuO 4
journal, June 2003


Is Sr 2 RuO 4 a chiral p-wave superconductor?
journal, March 2009


Evaluation of Spin-Triplet Superconductivity in Sr 2 RuO 4
journal, January 2012

  • Maeno, Yoshiteru; Kittaka, Shunichiro; Nomura, Takuji
  • Journal of the Physical Society of Japan, Vol. 81, Issue 1
  • DOI: 10.1143/JPSJ.81.011009

Crystal growth of Sr2RuO4
journal, August 2000


Coexistence of Superconductivity and Ferromagnetism in Two Dimensions
journal, July 2011


Unconventional vortex dynamics in superconducting states with broken time-reversal symmetry
journal, April 2002


Dynamical Superconducting Order Parameter Domains in Sr2RuO4
journal, November 2006


Observation of broken time-reversal symmetry in the heavy-fermion superconductor UPt3
journal, July 2014


Pairing symmetry and dominant band in Sr 2 RuO 4
journal, June 2014


Time-reversal symmetry-breaking superconductivity in Sr2RuO4
journal, August 1998

  • Luke, G. M.; Fudamoto, Y.; Kojima, K. M.
  • Nature, Vol. 394, Issue 6693
  • DOI: 10.1038/29038

Enhancement of Superconductivity of Sr 2 RuO 4 to 3 K by Embedded Metallic Microdomains
journal, October 1998


Superconductivity in a layered perovskite without copper
journal, December 1994

  • Maeno, Y.; Hashimoto, H.; Yoshida, K.
  • Nature, Vol. 372, Issue 6506
  • DOI: 10.1038/372532a0

Chiral p-wave order in Sr 2 RuO 4
journal, March 2012


Nucleation of Vortex State in Ru-Inclusion in Eutectic Ruthenium Oxide Sr 2 RuO 4 –Ru
journal, May 2010

  • Kaneyasu, Hirono; Sigrist, Manfred
  • Journal of the Physical Society of Japan, Vol. 79, Issue 5
  • DOI: 10.1143/JPSJ.79.053706

Strong peak in T c of Sr 2 RuO 4 under uniaxial pressure
journal, January 2017


Suppression of Proximity Effect and the Enhancement of p -Wave Superconductivity in the Sr 2 RuO 4 -Ru System
journal, December 2009


Vortices in chiral, spin-triplet superconductors and superfluids
journal, July 2009


Evidence from tunneling spectroscopy for a quasi-one-dimensional origin of superconductivity in Sr 2 RuO 4
journal, October 2013


Absence of an Isotope Effect in Superconducting Ruthenium
journal, March 1961


The superconductivity of Sr 2 RuO 4 and the physics of spin-triplet pairing
journal, May 2003


Mobile metallic domain walls in an all-in-all-out magnetic insulator
journal, October 2015


Probing multiband superconductivity by point-contact spectroscopy
journal, March 2010