Improvement of the LIDT of high-reflection mirrors

Dr. Sina Malobabic

Director of R&D
LASER COMPONENTS Germany GmbH

Title of Presentation:
Improvement of the LIDT of high-reflection mirrors with inserted quantized nanolaminates manufactured by ion beam sputtering

28 January 2025 • 9:05 AM - 9:25 AM PST
Oral Presentation
Conference: Opto 2025, San Francisco, California, United States
Moscone West, Room 2014 (Level 2)

08 May 2025 • 12:00 PM - 1:30 PM UTC+2
Oral Presentation
Conference: Ocla - 10th Symposium on Optical Coatings for Laser Applications
Vilnius, Lithuania

Abstract - Quantized nanolaminates

Quantized nanolaminates (QNLs) are sequences of alternating layer stacks of high and low refractive index material in the nanometer regime (quantum well layer and barrier layer) resulting in a metamaterial. It has been shown that QNLs are able to overcome the natural interdependency between refraction index and optical bandgap in the deposition material, allowing both properties to be tuned individually. Beyond that, QNLs are said to improve the laser-induced damage threshold (LIDT), while tuning the optical bandgap to higher values. In this study, we used ion beam sputtering (IBS) and embedded QNLs into a Ta₂O₅ - SiO₂ high-reflectance (HR) mirror at 532 nm and 45° angle of incidence. The thickness of the quantum well layers varied from 0,5 nm, 1 nm, 2 nm, 4 nm, 8 nm. LIDT was determined by S-on-1 testing. We also performed an evaluation of the electric field intensity throughout the whole extent of the mirrors to better understand the impact of QNL-dimensions on the endurance of HR-mirrors.

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