2019/05/03 by T. Valla, I. K. Drozdov, G. D. Gu · 26 citations
Materials Science · Physics and Astronomy · #Angle-resolved photoemission spectroscopy #Coupling (piping) #Cuprate #Doping #Fermi surface #Iron-based superconductors research #Photoemission spectroscopy #Physics of Superconductivity and Magnetism #Renormalization #Superconductivity #Superconductivity in MgB2 and Alloys #cond-mat.supr-con
paper · pdf · doi:10.1038/s41467-020-14282-4
published in Nature Communications 11(1), 569 (Nature Portfolio) · 8 pages, 4 figures
arxiv created 2019/05/03 · openalex created_date 2019/05/09 · openalex publication_date 2020/01/29 · arxiv updated 2020/02/03 · openalex updated_date 2026/08/05
Abstract In cuprate superconductors, superconductivity is accompanied by a plethora of orders and phenomena that complicate our understanding of superconductivity in these materials. Prominent in the underdoped regime, these orders weaken or vanish with overdoping. Here, we approach the superconducting phase from the more conventional overdoped side. We present angle-resolved photoemission spectroscopy studies of Bi 2 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math> Sr 2 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math> CaCu 2 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math> O 8+δ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mrow/><mml:mrow><mml:mn>8</mml:mn><mml:mo>+</mml:mo><mml:mi>δ</mml:mi></mml:mrow></mml:msub></mml:math> , cleaved and annealed in ozone to increase the doping all the way to the non-superconducting phase. We show that the mass renormalization in the antinodal region of the Fermi surface that possibly reflects the pairing, weakens with doping and completely disappears precisely where superconductivity disappears. This is the evidence that in the overdoped regime, superconductivity is determined primarily by the coupling strength. A doping dependence and an abrupt disappearance above the transition temperature eliminate phononic mechanism of the observed renormalization and identify the onset of spin-fluctuations as its likely origin.