Evidence for a delocalization quantum phase transition without symmetry breaking in CeCoIn 5

• DOI: 10.1126/science.aaz4566
• Publication Date: 2022-01-06T18:56:16Z
• Authors: Nikola Maksimovic; Daniel H. Eilbott; Tessa Cookmeyer; Fanghui Wan; Jan Rusz; Vikram Nagarajan; Shannon C. Haley; Eran Maniv; Amanda Gong; Stefano Faubel; Ian M. Hayes; Ali Bangura; John Singleton; Johanna C. Palmstrom; Laurel Winter; Ross McDonald; Sooyoung Jang; Ping Ai; Yi Lin; Samuel Ciocys; Jacob Gobbo; Yochai Werman; Peter M. Oppeneer; Ehud Altman; Alessandra Lanzara; James G. Analytis
• Keywords: Fractionalization; Quantum phases

The study of quantum phase transitions that are not clearly associated with broken symmetry is a major effort in condensed matter physics, particularly regard to the problem high-temperature superconductivity, for which such thought underlie mechanism superconductivity itself. Here we argue putative critical point prototypical unconventional superconductor CeCoIn5 characterized by delocalization electrons transition connects two Fermi surfaces different volumes, no apparent symmetry. Drawing on established theory f-electron metals, discuss an interpretation involves fractionalization spin and charge, model effectively describes anomalous transport behavior measured Hall effect.