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arXiv · 2411.15679

Large tuning of the optical properties of nanoscale NdNiO3 via electron doping

Yeonghoon Jin·Teng Qu·Siddharth Kumar·Nicola Kubzdela·Cheng-Chia Tsai·Tai De Li·Shriram Ramanathan·Nanfang Yu·Mikhail A. Kats
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Abstract

We synthesized crystalline films of neodymium nickel oxide (NdNiO3), a perovskite quantum material, switched the films from a metal phase (intrinsic) into an insulator phase (electron-doped) by field-driven lithium-ion intercalation, and characterized their structural and optical properties. Time-of-flight secondary-ion mass spectrometry (ToF-SIMS) showed that the intercalation process resulted in a gradient of the dopant concentration along the thickness direction of the films, turning the films into insulator-metal bilayers. We used variable-angle spectroscopic ellipsometry to measure the complex refractive indices of the metallic and insulating phases of NdNiO3. The insulator phase has a refractive index of n ~ 2 and low absorption in the visible and near infrared, and analysis of the complex refractive indices indicated that the band gap of the insulating phase is roughly 3-4 eV. Electrical control of the optical band gap, with corresponding large changes to the optical refractive indices, creates new opportunities for tunable optics.

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Yeonghoon Jin, Teng Qu, Siddharth Kumar, Nicola Kubzdela, Cheng-Chia Tsai, Tai De Li, Shriram Ramanathan, Nanfang Yu, Mikhail A. Kats. 2024-11-24. Large tuning of the optical properties of nanoscale NdNiO3 via electron doping. https://arxiv.org/abs/2411.15679

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