Nature and evolution of incommensurate charge order in manganites visualized with cryogenic scanning transmission electron microscopy
Abstract
Charge order is a modulation of the electron density and is associated with unconventional phenomena, including colossal magnetoresistance and metal–insulator transitions. Determining how the lattice responds provides insights into the nature and symmetry of the ordered state. Scanning transmission electron microscopy can measure lattice displacements with picometer precision, but its use has been limited to room-temperature phases only. Here, we demonstrate high-resolution imaging at cryogenic temperature and map the nature and evolution of charge order in a manganite. We uncover picometer-scale displacive modulations whose periodicity is strongly locked to the lattice and visualize temperature-dependent phase inhomogeneity in the modulations. These results pave the way to understanding the underlying structure of charge-ordered states and other complex phenomena.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 30, 2018
- Source ID
- 10.1073/pnas.1714901115
Entities
People
- Alemayehu S. Admasu
- Benjamin H. Savitzky
- Ismail El Baggari
- Jaewook Kim
- Lena F Kourkoutis
- Robert Hovden
- Sang-Wook Cheong
Organizations
- Air Force Office of Scientific Research
- Cornell University
- Gordon and Betty Moore Foundation
- National Science Foundation
- Rutgers University