Terahertz electro-optic Kerr effect in LaAlO3

Sergey Kovalev; Changqing Zhu; Anneke Reinold; Max Koch; Zirui Wang; Patrick Pilch; Ahmed Ghalgaoui; Siyu Duan; Cong Li; Jianbing Zhang; Pu Yu; Zhe Wang

arXiv · 2501.04346

Terahertz electro-optic Kerr effect in LaAlO3

Sergey Kovalev·Changqing Zhu·Anneke Reinold·Max Koch·Zirui Wang·Patrick Pilch·Ahmed Ghalgaoui·Siyu Duan·Cong Li·Jianbing Zhang·Pu Yu·Zhe Wang

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Abstract

In this letter, we investigate the terahertz (THz) electro-optic Kerr effect (KE) dynamics in LaAlO3 (LAO), a widely used substrate for thin film preparation. We show that the KE dynamics strongly depend on the material anisotropy due to interference between THz field-induced and strain-induced optical birefringence. Such interference leads to quasi-phase matching conditions of the KE, which becomes strongly frequency dependent. Depending on the THz frequency, the KE exhibits a uni- and bipolar shape of the quadratic response. The demonstrated effects will be present in a wide variety of materials used as substrates in different THz-pump laser-probe experiments and need to be considered in order to disentangle the different contributions to the measured ultrafast dynamic signals.

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Sergey Kovalev, Changqing Zhu, Anneke Reinold, Max Koch, Zirui Wang, Patrick Pilch, Ahmed Ghalgaoui, Siyu Duan, Cong Li, Jianbing Zhang, Pu Yu, Zhe Wang. 2025-01-08. Terahertz electro-optic Kerr effect in LaAlO3. https://arxiv.org/abs/2501.04346

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