Periodic Domain Inversion in Single Crystal Barium Titanate‐on‐Insulator Thin Film

• DOI: 10.1002/advs.202406248
• Publication Date: 2024-09-19T09:55:45Z
• Authors: Pragati Aashna; Hong‐Lin Lin; Yu Cao; Yuhui Yin; Yuan Gao; Sakthi Sanjeev Mo...; Di Zhu; Aaron Danner
• Keywords: Barium titanate; Strontium titanate

Abstract Experimentally achieving the first‐ever electric field periodic poling of single crystal barium titanate oxide (BTO, or BaTiO 3 ) thin film on‐insulator is reported. Owing to outstanding optical nonlinearities BTO, this result a key step toward quasi‐phase‐matching (QPM). First, BTO grown on dysprosium scandate substrate using pulsed laser deposition with layer strontium ruthenate later serving as bottom electrode for poling. The characterization x‐ray diffraction (XRD) and piezo‐response force microscopy demonstrate crystal, domain growth that enables desired poling, are presented. To investigate quality, both non‐destructive piezo response destructive etching‐assisted scanning electron (SEM) applied, it shown high uniform, intransient 50% duty cycle periods ranging from 2 µm 10 achieved. successful realization in unlocks potential highly efficient nonlinear processes under QPM seemed far‐fetched prior polycrystalline films which predominantly relied efficiency‐limited random non‐phase matching conditions integration photonic devices.