Coupling Between Electrons and Charge Density Wave Fluctuation and its Possible Role in Superconductivity
In most charge density wave (CDW) systems of different material classes, ranging from traditional correlated systems in low-dimension to recent topological systems with Kagome lattice, superconductivity emerges when the system is driven toward the quantum critical point (QCP) of CDW via external parameters of doping and pressure. Despite this rather universal trend, the essential hinge between CDW and superconductivity has not been established yet. Here, the evidence of coupling between electron and CDW fluctuation is reported, based on a temperature- and intercalation-dependent kink in the angle-resolved photoemission spectra of 2H-Pd<sub>x</sub>TaSe<sub>2</sub>. Kinks are observed only when the system is in the CDW phase, regardless of whether a long- or short-range order is established. Notably, the coupling strength is enhanced upon long-range CDW suppression, albeit the coupling energy scale is reduced. Interestingly, the estimation of the superconducting critical temperature by incorporating the observed coupling characteristics into McMillan's equation yields results closely resembling the known values of the superconducting dome. The results thus highlight a compelling possibility that this new coupling mediates Cooper pairs, which provides new insights into the competing relationship not only for CDW but also for other competing orders.
Authors
- Changyoung Kim
- Soonsang Huh (ORCID: https://orcid.org/0000-0002-5555-425X)
- Yeahan Sur (ORCID: https://orcid.org/0000-0003-0919-7412)
- Younsik Kim
- Jounghoon Hyun (ORCID: https://orcid.org/0000-0003-2254-4984)
- Yeonghoon Lee (ORCID: https://orcid.org/0000-0003-1040-7181)
- Kiyohisa Tanaka (ORCID: https://orcid.org/0000-0003-2779-5870)
- Yeongkwan Kim (ORCID: https://orcid.org/0000-0003-1408-0550)
- Dong-Hui Lu (ORCID: https://orcid.org/0000-0002-9708-0443)
- S. Ideta (ORCID: https://orcid.org/0000-0003-0877-7319)
- Chan‐young Lim (ORCID: https://orcid.org/0000-0001-7354-6600)
- Makoto Hashimoto (ORCID: https://orcid.org/0000-0003-1689-8997)
- Jaehun Cha (ORCID: https://orcid.org/0000-0002-9072-0954)
- Sunghun Kim (ORCID: https://orcid.org/0000-0001-9320-7243)
- Kee Hoon Kim (ORCID: https://orcid.org/0000-0003-2402-3111)
Institutions
- Hiroshima University (JP)
- Seoul National University (KR)
- Korea Advanced Institute of Science and Technology (KR)
- Korea Research Institute of Standards and Science (KR)
- SLAC National Accelerator Laboratory (US)
- Institute for Basic Science (KR)
- Stanford Synchrotron Radiation Lightsource (US)
- Institute for Molecular Science (JP)
- Ajou University (KR)
Publication Details
- Journal
- Advanced Science
- Published
- 2024-09-05
- DOI
- https://doi.org/10.1002/advs.202406043
- Citations
- 1
- Primary Topic
- Physics of Superconductivity and Magnetism
- Type
- article
- Field-Weighted Citation Impact
- 0.31
Funders
- U.S. Department of Energy
- Ministry of Education
- National Research Foundation
- Seoul National University
- Ajou University
- Korea Research Institute of Standards and Science
- National Research Foundation of Korea
- Ministry of Science and ICT, South Korea
- Office of Science
- Basic Energy Sciences
- SLAC National Accelerator Laboratory