Design and experimental evaluation of TiO\(_2\)/MgF\(_2\) dual-layer anti-reflection coatings for Nd- and Er-doped phosphate glass lasers

Van Dai Le; Thanh Tung Do; Pham Duc Tuan; Hong Giang Truong

doi:10.15625/0868-3166/22927

Author affiliations

Authors

Le Van Dai Academy of Military Science and Technology, 17 Hoang Sam, Nghia Do, Hanoi, Vietnam
Do Thanh Tung Institute of Technical Physics, 17 Hoang Sam, Nghia Do, Hanoi, Vietnam https://orcid.org/0000-0002-6967-9512
Pham Duc Tuan Academy of Military Science and Technology, 17 Hoang Sam, Nghia Do, Hanoi, Vietnam https://orcid.org/0009-0002-7511-0506
Truong Hong Giang Academy of Military Science and Technology, 17 Hoang Sam, Nghia Do, Hanoi, Vietnam

DOI:

https://doi.org/10.15625/0868-3166/22927

Keywords:

Anti-reflection, AR Coating, Nd-Doped, Er-Doped, Laser

Abstract

This study focuses on the design and experimental evaluation of two-layer TiO\(_2\)-MgF\(_2\) anti-reflection (AR) coatings on Nd- and Er-doped phosphate glass for laser applications at 1053 nm and 1535 nm. Using matrix theory and TFCalc software, the optimized design achieves reflectance close to 0% for Nd-doped glass and below 0.1% for Er-doped glass. The coatings were fabricated using the SYRUSpro 710 system, achieving experimental transmittance values of 99.7% in the 1050–1080 nm range and 99.8% in the 1530–1570 nm range, despite minor discrepancies between experimental and simulated results. The coating durability meets MIL-SPEC standards for mechanical testing. Additionally, laser-induced damage threshold (LIDT) measurements at 1064 nm yielded a 50% damage fluence of 13.2 J/cm² for the Nd-doped sample, demonstrating reliable laser resistance suitable for moderate-fluence solid-state laser applications. This research lays the foundation for optimizing coating processes and advancing the development of rare-earth-doped solid-state laser sources.

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