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arXiv · 2501.14181

Nonlinear optical response in a ferromagnetic insulating manganite: Pr$_{0.8}$Ca$_{0.2}$MnO$_{3}$

A. Nakano·K. Uchida·Y. Tomioka·M. Takaya·Y. Okimoto·K. Tanaka
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Abstract

High harmonic generation from Pr$_{0.8}$Ca$_{0.2}$MnO$_{3}$ was investigated across a high-temperature paramagnetic phase and a low-temperature ferromagnetic phase. As the temperature decreases, the harmonic intensity gradually increases in the paramagnetic phase like that in different composition material Pr$_{0.6}$Ca$_{0.4}$MnO$_{3}$. However, it turns to a decrease in the ferromagnetic phase. We propose a possible interpretation of the anomaly around the ferromagnetic transition temperature considering the thermal fluctuation of orbital order and the metal-insulator phase separation in the ferromagnetic insulating phase.

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A. Nakano, K. Uchida, Y. Tomioka, M. Takaya, Y. Okimoto, K. Tanaka. 2025-01-24. Nonlinear optical response in a ferromagnetic insulating manganite: Pr$_{0.8}$Ca$_{0.2}$MnO$_{3}$. https://arxiv.org/abs/2501.14181

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