From Order to Disorder: Tailoring Laser Materials for Next-Generation Ultrafast Photonics

Ultrafast lasers generating femtosecond pulses have become essential tools in micromachining, biomedical applications, nonlinear optics, and time-resolved spectroscopy. The performance of these systems is increasingly governed by the properties of the gain medium, where engineered disorder in laser materials provides a powerful degree of freedom to tailor spectral bandwidth, pulse dynamics, and thermal characteristics—enabling the development of next-generation ultrafast laser systems.

In this webinar, hosted by the Fundamental Laser Sciences Technical Group, Pavel Loiko will present recent advances in engineering the broadband emission properties of rare-earth-doped laser materials for few-optical-cycle pulse generation in mode-locked lasers, with a particular focus on the eye-safe 2 µm spectral region. The talk will explore strategies to induce inhomogeneous spectral broadening—including ion clustering, structural disorder, and compositional disorder in solid-solution ("mixed") compounds. The role of electron-phonon interaction in shaping long-wavelength vibronic gain will also be discussed. Key achievements in the development of sub-100 fs lasers at 2 µm will be highlighted, along with future prospects for mode-locked laser systems operating in the mid-infrared.

Subject Matter Level: Intermediate - Assumes basic knowledge of the topic

What You Will Learn:
• Advanced spectroscopy of laser materials
• Key enabling elements of passively mode-locked lasers
• Criteria for choosing gain materials for mode-locked lasers

Who Should Attend:
• Everyone interested in (ultrafast) solid-state lasers
• From graduate students and early-career researchers to senior academics
• Industry representatives

About the Presenter: Pavel Loiko from University of Caen Normandy

Pavel Loiko received his PhD in Optics from Belarusian State University in 2012 and his Habilitation (HDR) from the University of Caen Normandy, France, in 2023. Since 2017, he has been a Research Fellow at the CIMAP (Center for Ions, Materials and Photonics) CNRS research laboratory, where his work focuses on developing novel optical materials—such as crystals, ceramics, and glass fibers—for bulk, waveguide, and fiber lasers spanning the visible to mid-infrared spectrum, including ultrashort-pulse systems. He has supervised five PhD students and currently serves as a Topical Editor for JOSA B (Optica Publishing Group) and as a committee member for the Advanced Solid-State Lasers (Optica) and Europhoton (European Physical Society) conferences. He has co-authored over 100 scientific publications in optics, laser physics, and materials science.