Description
Nearly four decades after the discovery of high-temperature superconductivity in cuprates, the pairing mechanism and the origin of the pseudogap remain unresolved. Over the years, the field has accumulated many competing theories and interpretations, often strongly defended by their proponents. This has made it increasingly difficult to reconsider established views and move beyond earlier assumptions. Renewed interest in cuprates offers an opportunity to revisit these questions, with the hope that a new generation of researchers, less attached to long-standing debates, can bring fresh perspectives to the field.
In this talk, I will revisit selected ARPES results and their interpretations, focusing on the role of spin fluctuations in superconducting pairing and the relationship between the pseudogap and electronic structure. In particular, I will discuss how the nesting of van Hove singularities may contribute to the pseudogap and how proximity to Lifshitz transitions correlates with superconductivity in both cuprate and iron-based superconductors. I will also consider whether such nesting and the resulting electronic instabilities can help explain the increase in the maximum superconducting transition temperature with the number of CuO₂ layers. Finally, I will suggest revisiting some less-explored features of cuprates, particularly the possible connection between the shadow band and altermagnetism, as well as the origin and role of incommensurate superstructures.
