Feb 2 (Fri) @ 12:00pm: ”Noise, Dynamics and Squeezed Light in Quantum Dot Lasers,” Frédéric Grillot, Prof., IP Paris & U. of New Mexico

Abstract

Semiconductor lasers have become ubiquitous in both scientific research and engineering applications, and their miniaturization has made significant strides since their initial demonstration in 1960. Prominent advancements in this domain include the development of quantum dot (QD) lasers. In the current landscape of optoelectronics, photonic integrated circuits (PICs) play also a pivotal and far-reaching role. They offer unmatched scalability, reduced weight, cost-effectiveness, and energy efficiency by enabling the fabrication of complete optical systems using versatile building blocks seamlessly integrated onto a single chip. In this context, the direct epitaxial growth of III-V materials on silicon holds promise as a compelling approach for the development of coherent laser sources. Noise considerations are indeed paramount when it comes to assessing the quality and reliability of technologies. Achieving the shot noise limit and the Schawlow-Townes linewidth has long been recognized as significant milestones. To tackle noise issues, a range of noise reduction techniques has been explored, encompassing passive optical feedback within an external cavity and active electronic feedback mechanisms to compensate for injection current fluctuations. However, while feedback systems can mitigate laser noise, they can also introduce more intricate nonlinear dynamics. The presentation will showcase that QD lasers are found to exhibit a high degree of robustness when exposed to parasitic optical reflections but manifest an increased sensitivity to optoelectronic feedback.  Furthermore, recent advancements in low-noise pumping circuits for lasers have led to the generation of amplitude-squeezed light. This represents a transition from classical noise to quantum noise, opening up new possibilities in the field of laser technology and quantum optics. The presentation will also highlight that QD lasers can exhibit broadband squeezing bandwidth and a significant level of squeezing at room temperature. All these outcomes contribute to a deeper comprehension of the characteristics of QD lasers, laying the groundwork for the development of high-performance classical and quantum emitters on PICs in the future.

Bio

Frédéric Grillot is currently a Full Professor at Télécom Paris (France) and a Research Professor at the University of New-Mexico (USA). His research interests include, but are not limited to, advanced quantum confined devices using III-V compound semiconductors, quantum dots quantum dashes, light-emitters based on intersubband transitions, non-classical light, nonlinear dynamics and optical chaos in semiconductor lasers systems as well as microwave and silicon photonics applications.

Hosted by: Professor John Bowers

Submitted by: Amy Donnelly <amymdonnelly@ucsb.edu>