"A piece of femto-galaxy"
by Min-Cheol Lee (Center for Correlated Electron Systems, IBS)
A single crystalline Ca2RuO4, destroyed by an ultrafast laser beam, is modeled as a workpiece. The broken crystal shows a clear line along the path of the femtosecond laser pulse incident on the sample. Unlike conventional techniques, ultrafast spectroscopy can instantaneously introduce a large amount of energy by using femtosecond light. Particularly in the case of Ca2RuO4 with a strong correlation between electronic/lattice structures, huge structural changes can arise, such that the sample is destroyed not by physical contact but merely by the absorption of ultrafast light. The millimeter-sized black sample with red glue reminds me of a vast galaxy in the night sky.
Spectroscopic Studies on the Metal–Insulator Transition Mechanism in Correlated Materials"
Min-Cheol Lee, So Yeun Kim and Changyoung Kim
(Center for Correlated Electron Systems, IBS)
SangJoon Choi (email@example.com)
Spectroscopic approaches to metal–insulator‐transition phenomena with incident and reflected light as well as photoemitted electrons are discussed by Changyoung Kim and co‐workers in article number 1704777. A correlated material with a periodic electronic potential in its insulating state (blue region) with localized electrons, and in metallic state (red region) is depicted.
- Frontipiece: https://onlinelibrary.wiley.com/doi/10.1002/adma.201870318