Guest Lecture - nonlinear optics on a CMOS platform

Abstract
The microelectronics industry is foundationally built on silicon-based
semiconductor devices. Silicon photonics, a relatively nascent yet rapidly emerging
field, leverages the maturity of CMOS foundry processes and promises dense
integration of optical functionality like that of microelectronic circuits. However,
silicon’s inability to produce gain or lase has presented a major barrier to
developing fully integrated silicon-based optoelectronic devices. In parallel,
nonlinear optics has made substantial advances in expanding the range of
accessible frequencies of optical sources, yet as a field has evolved largely
independently of silicon-based materials. By combining the principles of nonlinear
optics with scalable, high-quality linear optical elements enabled by silicon
photonics, such as waveguides, and electronic devices, such as CMOS-based
diodes, all on-chip, the latitude of the optoelectronic functionality of silicon can be
significantly enhanced. However, nonlinear optical processes such as sum
frequency generation and optical parametric amplification, which rely on the
second-order susceptibility, are forbidden in silicon, due to its crystalline inversion
symmetry. This symmetry can be broken with an applied electric field, a process
known as electric field induced second harmonic generation, which is effectively
derived from the third-order susceptibility of a material and can be understood as
four-wave mixing between two optical electromagnetic fields, one DC field, and a
resultant optical field. Moreover, quasi-phase matching allows for efficient power
transfer between these fields, which can be implemented in silicon using
periodically-poled DC fields generated by reverse-biased PN diodes. In this
presentation, I will discuss the design and characterization of devices that utilize
industry-ready silicon photonics foundry processes to realize nonlinear optics onchip
via second harmonic generation and the first (second-order) optical
parametric amplifier on silicon

Bio
David received the BS and MS degrees from Northwestern University (Evanston, Ill.,
United States) in 2016, under the direction of renowned Professor Manijeh RAZEGHI,
who leads the Center for Quantum Devices. He received his PhD degree from
Stanford University (Stanford, Calif., United States) in 2023. He is currently working at
Lightmatter while also undertaking a staff appointment in the same group where he
did his PhD with Professor Hideo MABUCHI, known for his pioneering work in
quantum feedback.