PHOTONIC DEVICES LABORATORY
We are interested in pushing the boundaries of laser-matter interactions to develop cutting-edge optical devices and micro/nanofabrication technologies. Our work bridges fundamental science with technological innovation at the intersection of photonics, nanotechnology, and materials science, tackling long-standing challenges in advanced laser writing, nonlinear interactions, and integrated photonics. Through a combination of state-of-the-art experimental techniques with theoretical insights, we develop laser-based fabrication methods, driving breakthroughs in three-dimensional (3D) laser micro-lithography, 3D holography, laser nanofabrication, and 3D photonics. Key contributions include the invention of the in-chip photonics paradigm, integrated-optical elements embedded to silicon, groundbreaking advances in laser nanofabrication inside silicon, the invention of true-to-life holography, and the development of multi-functional chips and 3D optical systems.
A significant effort is geared towards providing solutions to technological problems. We demonstrated a novel micro-fabrication method deep inside silicon wafers, enabling truly 3D laser-written elements enabling “in-chip” functionalities. This is similar to direct fabrication of 3D objects, commonly referred to as 3D printing, capturing the public imagination on a scale rapidly approaching that of consumer electronics revolutions of the last decades. We also introduced the first 3D Si-photonics elements directly inside the wafer, without altering wafer surface (Tokel et al, Nature Photon., 2017).
Recently, we introduced a ground-breaking nanofabrication paradigm inside Si, achieving resolution far below the diffraction limit, down to 100 nm (Nature Commun. 2024). By employing spatial beam modulation, we drive nonlinear feedback mechanisms and plasmonic interactions within the bulk, enabling subwavelength modulation and unprecedented 3D nanoscale functionality. The work leverages seeding-based interactions that propagate nanostructures, laser polarization as a novel tool for controlling nanoscale symmetry, and introduces the first in-chip nanophotonics functionality. We anticipate these to have significant implications for electronics, Si-photonics, photovoltaics, and MEMS/NEMS, — industries collectively exceeding $500 billion in annual revenue. We anticipate these advances to pave the way for transformative opportunities in 3D nanophotonics, multi-functional chips, and enhanced electronic-photonic integration, toward a new wave of innovation in semiconductor technologies.
Onur Tokel