Cascade laser optimization for 3 H 4 → 3 H 5 and 3 F 4 → 3 H 6 sequent transitions in Tm 3+ -doped materials

Hippolyte Dupont (1) , Lauren Guillemot (2) , Pavel Loiko (2) , Rosa Maria Solé (3) , Xavier Mateos (3) , Magdalena Aguiló (3) , Francesc Díaz (3) , Alain Braud (2) , Patrice Camy (2) , Patrick Georges (1) , Frédéric Druon (1)

1 Laboratoire Charles Fabry / Lasers
2 CIMAP - UMR 6252 - Centre de recherche sur les Ions, les MAtériaux et la Photonique
3 FiCMA - Física i Cristal·lografia de Materials i Nanomaterials

We study a cascade laser scheme involving the 3 H 4 → 3 H 5 and 3 F 4 → 3 H 6 consecutive transitions in Tm 3+ -doped materials as a promising technique to favor laser emission at 2.3 µm. We examine the conditions in terms of the Tm 3+ doping levels for which the cascade laser is beneficial or not. For this, Tm:LiYF 4 lasers based on crystals with several doping levels in the range of 2.5 - 6 at.% with and without cascade laser are studied. For low doping of 2.5 at.% Tm 3+ , adding the laser emission at 1.9 µm allows to double the output power at 2.3 µm, whereas for high doping of 6 at.%, allowing the laser to operate at 1.9 µm totally suppresses the laser emission at 2.3 µm. An analytical model is developed and confronted with experimental results to predict this doping-dependent phenomenon and forecast the potential benefits. This study of cascade laser emission on the 3 H 4 → 3 H 5 and 3 F 4 → 3 H 6 transitions versus the Tm 3+ doping level is finally extended to other well-known Tm 3+ -doped laser materials.

Domains: Physics [physics]

Hippolyte Dupont, Lauren Guillemot, Pavel Loiko, Rosa Maria Solé, Xavier Mateos, et al.. Cascade laser optimization for 3 H 4 → 3 H 5 and 3 F 4 → 3 H 6 sequent transitions in Tm 3+ -doped materials. Optics Express, 2023, 31 (21), pp.34201. ⟨10.1364/OE.501585⟩. ⟨hal-04247277⟩