This project is jointly funded by the Electronics, Photonics, and Magnetic Devices Program (EPMD) in the Division of Electrical, Communications and Cyber Systems (ECCS) and the Electronic and Photonic Materials Program (EPM) in the Division of Materials Research (DMR).
In this research non-linear photonic crystal (PhC) waveguide devices are being developed. Of particular interest are sub-terahertz PhC electro-optic modulators (EOM). This work builds on our recent demonstration of non-linear PhC EOMs with a bandwidth greater than 50 GHz. Based on recent device simulations non-linear PhC waveguide modulators are being designed and fabricated for sub-terahertz frequency and low-voltage (0.5V-mm) operation. To operate at low voltage, and wide bandwidth, ferroelectric BaTiO3 with large electro-optic coefficients are required. To minimize bandwidth limitations due to microwave losses, PhC and slow light concepts are utilized. Devices are fabricated using vapor phase epitaxial deposition, and both conventional photolithography and focused ion beam milling. Factors limiting bandwidth including microwave loss, optical/microwave velocity mismatch and device length are determined through modeling and testing. Chip-scale integration of these PC devices with a single platform is being pursued using epitaxial BaTiO3 on Si.
By using non-linear photonic crystals with large optical non-linearities, significant improvements in bandwidth, operating voltage, and size are expected compared to conventional electro-optic devices. It is anticipated that these devices should have excellent photo and thermal stability. The broader impact is the potential realization of sub-terahertz bandwidth, sub-millimeter size optical devices and photonic circuits for optical communications and information processing. The project will involve training of undergraduates, and graduate students in the area of nanophotonics as well as mentoring K-12 students. Outreach through industrial and government lab internships of doctoral students is involved.
