Scalable approach for continuous-wave deep-ultraviolet laser at 213nm.

Yushi Kaneda,Toshiaki Sasa,Junji Hirohashi,Yasunori Furukawa,Masahiro Sasaura,Tsuyoshi Tago,Hiroaki Nakao

doi:10.1364/oe.27.008021

Abstract

We present a novel approach for generation at 213nm in continuous-wave, corresponding to the fifth harmonic of common 1064nm laser, in pure continuous-wave mode. The approach is scalable in output power. Starting from two infrared fiber laser sources, we demonstrated 0.456W output at 213nm.

Highlights

The thulium-doped fiber amplifier (TDFA) is an in-house, single-stage clad-pumped amplifier, and is seeded by an in-house, single-frequency fiber laser oscillator at 1907nm with an output power of 40mW
Since all 3 interacting beams are all in the same polarization, the Brewster-cut end facets are effective for low loss resonator as well as for low-loss outcoupling of the generated 852nm
With up to 4.02W of 852nm available for the harmonic generation, 2.41W of 426nm was obtained from the first external resonant doubler containing 20mm long type-I LBO cut at φ=90°, θ=27.4° for the type-I critical phasematching at room temperature

Summary

Introduction

The thulium-doped fiber amplifier (TDFA) is an in-house, single-stage clad-pumped amplifier, and is seeded by an in-house, single-frequency fiber laser oscillator at 1907nm with an output power of 40mW. Pumped with two 9-W multimode diode lasers at 793nm, it gives an output power of approximately 5W. The seed laser at 1907nm is free running and does not have the frequency control capability.

Results

Conclusion