Work

Flatness-insensitive pulsed electric current bonding of sapphire/Nd:YAG ceramics

Year: 2025

Type: article

Abstract: Initial surface-flatness-insensitive bonding of sapphire and YAG ceramics for high-average-power laser materials was achieved via pulsed electric current bonding (PECB), a type of thermal diffusion bonding. Nd:YAG ceramics with surface flatness of λ/10, λ/5, and λ (λ = 632.8 nm) were bonded to sapphire (flatness < λ/10). All samples exhibited excellent optical performance irrespective of initial flatness. In-line transmittance approached theoretical limits, transmitted wavefront distortion was below 0.264λ, and polarization exceeded 35 dB. Minor unbonded regions appeared near edges for λ-flat samples, but overall performance remained unaffected. TEM analysis revealed interfacial microstructures, providing deeper insights. These findings demonstrate that PECB enables high-quality bonding with minimal dependence on initial flatness, making it advantageous for manufacturing large-aperture, high-average-power, and high-pulse-energy laser materials.

Source: Optical Materials Express

DOI: 10.1364/ome.575741

Authors: Hiroaki Furuse, Hiroyuki Tanaka, Yuki Kagami, Hiyori Uehara, Ryo Yasuhara

Institutions: Kitami Institute of Technology, National Institute for Fusion Science

Language: English

Topic: Solid State Laser Technologies

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,843

Funder: National Institute for Fusion Science