Seminarium Fizyki Politechniki Wrocławskiej
PWr, bud. A1, sala 322
Integrated lithium niobate platform for classical and quantum nonlinear optics
dr Hubert Stokowski
Department of Applied Physics and Ginzton Laboratory, Stanford University
On-chip integrated photonic devices constitute the backbone of the systems we use to interface with technology. Semiconductor devices enable the transmission of information from every modern smartphone, wearable device, home appliance, and car directly to our eyes. On the other hand, an increasing number of consumer electronics use photonic components to collect information necessary for their functions, such as face recognition in phones, health monitoring in wearables, and autonomous driving. Moreover, integrated photonics is common in specialized applications like data centers, the internet, pollution monitoring, and medical diagnostics. Developing new types of integrated light sources will enable unexplored applications and advances in the existing ones.
In this talk, I will describe our recent advancements in developing chip-integrated nonlinear optical light sources using lithium niobate. Nonlinear optics studies photon interactions through the intrinsic properties of the materials in which they propagate. It provides a versatile alternative to existing semiconductor technologies for light source engineering. We have designed and fabricated devices that generate second-harmonic and enable tunable optical parametric oscillation with high efficiency and at low power. Our platform allows light generation from UV to mid-infrared, with lithography controlling the design wavelength. It also opens the door to novel chip-integrated light sources such as comb generators and squeezers. By combining the electro-optic capabilities of lithium niobate with our nonlinear optics platform, we create an on-chip frequency-modulated optical parametric oscillator. It produces a flat-top frequency comb composed of hundreds of distinct frequencies, ideal for applications in spectroscopy and telecommunication. Finally, we utilize lithium niobate to generate squeezed light within a complex photonic integrated circuit and employ it as a quantum-enhanced sensor.