Lasing with conical diffraction feature in the KGd(WO 4 ) 2 :Nd biaxial crystal

Alain Brenier (1)

1 ILM - Institut Lumière Matière [Villeurbanne]

With an experimental setup designed to record simultaneously the far field and the near field patterns, we got lasing with feature of conical diffraction in the biaxial Nd 3+-doped KGd(WO 4) 2 crystal. The key-point is that the lasing direction is not single and is constituted by an angular distribution including the optical axis. Very slight changes of crystal orientation leads to crescent shape 1068 nm light distributions in the near field. The beam launched towards the biaxial crystal is mainly linear polarized with its intensity in agreement with the Nd fluorescence angular distribution. A theoretical background is provided, including the monoclinic and triclinic symmetries and laser amplification including elliptical modes and cavity round trip.

Mots clés: conical diffraction; biaxial crystal; optical axis; diode pumped laser

Domaines: Optique [physics.optics]

Alain Brenier. Lasing with conical diffraction feature in the KGd(WO 4 ) 2 :Nd biaxial crystal. Applied Physics B - Laser and Optics, 2016, 122, pp.237. ⟨10.1007/s00340-016-6512-y⟩. ⟨hal-03363791⟩