Shanghai Jiao Tong University, China
Condensed matter systems are most interesting because their rich emergent phenomena that often can go against the simple rules thumbs derived from standard models. In this talk, I will introduce a poor man’s illustration of the concept of emergence. As an example, I will discuss our recent study of the rich magnetic and orbital ordering in the Fe-based high-temperature superconductors, and demonstrate a counter-intuitive phenomenon that a larger spin actually fluctuate stronger in the presence of itinerant carriers. This talk will also clarify the relation between the structural (orbital) order and the magnetic order. Finally, we point out an occurrence of correlated metals in such mixed local/non-local systems.