Dynamic competition between Cooper pair and spin density wave condensation
Quantum matter phases may coexist microscopically even when they display competing tendencies. A fundamental question is whether such a competition can be avoided through the elimination of one phase while the other one condenses into the ground state. Here, we present a high-resolution neutron spectroscopy study of the low-energy spin excitations in the high-temperature superconductor <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:msub><a:mi>La</a:mi><a:mrow><a:mn>1.855</a:mn></a:mrow></a:msub><a:msub><a:mi>Sr</a:mi><a:mrow><a:mn>0.145</a:mn></a:mrow></a:msub><a:msub><a:mi>CuO</a:mi><a:mn>4</a:mn></a:msub></a:mrow></a:math>. In the normal state, we find low-energy magnetic fluctuations at incommensurate reciprocal lattice positions where spin-density-wave order emerges at lower Sr concentration or at high magnetic fields. While these spin excitations are largely suppressed by the emergence of the superconducting spin gap, some low-energy magnetic fluctuations persist deep inside the superconducting state. We interpret this result in terms of a dynamic competition between superconductivity and magnetism, where superconductivity impedes the condensation of low-energy magnetic fluctuations through the formation of magnetically mediated Cooper pairs.
Authors
- T. Kurosawa (ORCID: https://orcid.org/0000-0001-5065-6823)
- N. Momono (ORCID: https://orcid.org/0000-0001-8408-8617)
- D. G. Mazzone (ORCID: https://orcid.org/0000-0002-0421-0625)
- J. Chang (ORCID: https://orcid.org/0000-0002-4655-1516)
- Oleh Ivashko (ORCID: https://orcid.org/0000-0002-4869-8175)
- Ch. Niedermayer (ORCID: https://orcid.org/0000-0001-6508-8988)
- Jacques Ollivier (ORCID: https://orcid.org/0000-0003-2806-8130)
- M. Pikulski
- Jaewon Choi (ORCID: https://orcid.org/0000-0003-4616-4345)
- N. B. Christensen (ORCID: https://orcid.org/0000-0001-6443-2142)
- Kim Lefmann (ORCID: https://orcid.org/0000-0003-4282-756X)
- H. M. Rønnow (ORCID: https://orcid.org/0000-0002-8832-8865)
- Linda Udby (ORCID: https://orcid.org/0000-0002-2816-6825)
- M. Oda (ORCID: https://orcid.org/0000-0002-5667-2856)
- J. Mesot
- B. Decrausaz (ORCID: https://orcid.org/0009-0007-3369-0801)
Institutions
- University of Copenhagen (DK)
- University of Zurich (CH)
- Hokkaido University (JP)
- Diamond Light Source (GB)
- ETH Zurich (CH)
- Muroran Institute of Technology (JP)
- Institut Laue-Langevin (FR)
- École Polytechnique Fédérale de Lausanne (CH)
- Technical University of Denmark (DK)
Publication Details
- Journal
- Physical Review Research
- Published
- 2025-05-09
- DOI
- https://doi.org/10.1103/physrevresearch.7.023131
- Citations
- 1
- Primary Topic
- Advanced Condensed Matter Physics
- Type
- article
- Field-Weighted Citation Impact
- 1.26
Funders
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- DanScatt