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arXiv · 1505.08086

Evidence of photo-induced dynamic competition of metallic and insulating phase in a layered manganite

Yuelin Li·Donald A. Walko·Qingan Li·Yaohua Liu·Stephan Rosenkranz·Hong Zheng·J. F Mitchell
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Abstract

We show evidence that the competition between the antiferromagetic metallic phase and the charge- and orbital-ordered insulating phase at the reentrant phase boundary of a layered manganite, LaSr2Mn2O7, can be manipulated using ultrafast optical excitation. The time-dependent evolution of the Jahn-Teller superlattice reflection, which indicates the formation of the charge and orbital order, was measured at different laser fluences. The laser-induced enhancement and reduction the Jahn-Teller reflection intensity shows a reversal of sign between earlier (~10 ns) and later (~150 ns) time delays during the relaxation after photo excitation. This effect is consistent with a scenario whereby the laser excitation modulates the local competition between the metallic and the insulating phases.

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Yuelin Li, Donald A. Walko, Qingan Li, Yaohua Liu, Stephan Rosenkranz, Hong Zheng, J. F Mitchell. 2015-05-29. Evidence of photo-induced dynamic competition of metallic and insulating phase in a layered manganite. https://doi.org/10.1088/0953-8984/27/49/495602

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