Tailoring of the free spectral range and geometrical cavity dispersion of a microsphere by a coating layer

Davor Ristic (1) , Maurizio Mazzola (2) , Andrea Chiappini (3) , Alphonse Lovamamy Rasoloniaina (4) , Patrice Féron (4) , Roberta Ramponi (5) , Giancarlo C. Righini (6) , Gilles Cibiel (7) , Mile Ivanda (8) , M. Ferrari (3)

1 IFN - CNR Institute for Photonics and Nanotechnologies
2 CSMFO - Caratterizzazione e Sviluppo di Materiali per la Fotonica e l'Optoelecttronica
3 CSMFO group
4 FOTON - Fonctions Optiques pour les Technologies de l'informatiON
5 POLIMI - Dipartimento di Fisica [Politecnico Milano]
6 IFAC - Istituto di Fisica Applicata "Nello Carrara"
7 CNES - Centre National d'Études Spatiales [Toulouse]
8 Rudjer Boskovic Institute [Zagreb]

The modal dispersion of a whispering gallery mode (WGM) resonator is a very important parameter for use in all nonlinear optics applications. In order to tailor the WGM modal dispersion of a microsphere, we have coated a silica microsphere with a high-refractive-index coating in order to study its effect on the WGM modal dispersion. We used Er3+ ions as a probe for a modal dispersion assessment. We found that, by varying the coating thickness, the geometrical cavity dispersion can be used to shift overall modal dispersion in a very wide range in both the normal and anomalous dispersion regime.

Mots clés: Opticalresonators; Rare-earth-dopedmaterials

Domaines: Optique [physics.optics]

Davor Ristic, Maurizio Mazzola, Andrea Chiappini, Alphonse Lovamamy Rasoloniaina, Patrice Féron, et al.. Tailoring of the free spectral range and geometrical cavity dispersion of a microsphere by a coating layer. Optics Letters, 2014, 39 (17), pp.5173. ⟨10.1364/OL.39.005173⟩. ⟨hal-01152633⟩