Abstract
We have investigated the dynamics of spin-state crossover (SSC) for perovskite through optical phonons by means of infrared and inelastic x-ray spectroscopy. Upon thermally induced SSC, anomalously dispersionless Co-O bond stretching phonons coupled to the thermally excited spin state have been identified. The enhanced spin-state fluctuation irrespective of the presence of a clear charge gap suggests the emergence of complex spin-state disproportionation involving low-, intermediate-, and high-spin states due to the strong correlation among thermally activated spin states.
- Received 16 April 2014
- Revised 26 July 2014
DOI:https://doi.org/10.1103/PhysRevB.90.081109
©2014 American Physical Society