Speaker
Description
Quantum computers based on neutral atoms hold great potential for revolutionary discoveries across research and industry. However, scaling these systems requires precise, real-time control of laser power to manipulate atomic qubits reliably. Integrated photonics – especially based on electro-optically active materials such as LTOI – has emerged as a platform to pulse laser light used to control atoms. Yet LTOI lacks integrated photodetectors, so on-chip optical signals cannot be monitored directly on the same chip.
In my master's thesis project, I address this by hybrid-integrating low-noise photodiodes, fabricated on a separate platform, directly onto LTOI photonic chips via flip-chip bonding to realize closed-loop feedback for setting the working point of light modulators.
Working principle: A small fraction of the on-chip optical power is tapped off and guided to the flip-chip bonded photodiode via a 3D-nanoprinted out-of-plane coupler. The resulting photocurrent is processed by a PID control system that continuously adjusts the modulator's working point, laying the foundation for compact, self-regulating photonic modules.
In this work, I present the complete process from optical design and simulation, through chip fabrication, to the micro-assembly challenges of combining these two heterogeneous photonic platforms into a single functional device.