令和 5年度（２０２３年度）第2回 物理教室談話会

題目	The cuprate phase diagram: contradictions and puzzles
講師	William Sacks 氏 (フランス ソルボンヌ大学教授)
日時	2023年7月18日（水）16:00-
場所	コラボレーション室（コラボレーション棟3階）
概要	Over the last few decades the temperature-doping (T-p) phase diagram is still highly debated. Two distinct classes of phase diagrams have emerged depending on the interpretation of the ‘pseudogap’ line T* and whether or not it crosses the Tc dome and extrapolates to some critical doping value. We will first review some main points about cuprate high-Tc, focusing on the enigmatic pseudogap phase, the T* line, and their interpretation. The discussion will draw upon experimental techniques such as ARPES and tunneling, specific heat, magnetic susceptibility, and NMR Knight shift. We then introduce the ‘pairon’ concept : pairs of holes bound by their local anti-ferromagnetic environment. We will show that both the superconducting and pseudogap phases can be explained within the pairon model and, furthermore, that a new type of condensation mechanism emerges based on the pairon-pairon spatial correlations. In this context a ‘universal’ phase diagram can finally be proposed.
世話人	世話人　横谷　尚睦（内線 7897）