A Barium Titanate-on-Oxide Insulator Optoelectronics Platform.

Area of Science:

• Materials Science
• Optoelectronics
• Photonics

Background:

• Electro-optic modulators are crucial for optical communication networks.
• Lithium niobate is a traditional material, but barium titanate offers superior nonlinear properties.
• Barium titanate thin film growth on magnesium oxide often results in degraded crystal quality.

Purpose of the Study:

• To identify suitable substrates for high-quality barium titanate thin films.
• To achieve vertical optical mode confinement in waveguide devices.
• To enable advanced on-chip optoelectronic applications.

Main Methods:

• Identification of scandate-based substrates.
• Evaluation of lattice mismatch and refractive index properties.
• Assessment of crystal quality and optical mode confinement.

Main Results:

• Scandate substrates exhibit small lattice mismatch with barium titanate.
• These substrates provide low refractive index for vertical mode confinement.
• High crystal quality of barium titanate thin films is achieved concurrently.

Conclusions:

• Scandate substrates offer a promising platform for barium titanate-based optical waveguide devices.
• This advancement facilitates nonlinear on-chip optoelectronics.
• Potential applications include Mach-Zehnder modulators, wavelength division multiplexing, and quantum optics-on-chip.