Waveguiding demonstration on Yb:Nb:RbTiOPO4/RbTiOPO4(001) epitaxies grown by LPE

Femtosecond-Laser Microstructuring of Ribs on Active (Yb,Nb):RTP/RTP Planar Waveguides

“…The real refractive indexes of the waveguide and the substrate in TM polarization were 1.8967 for the layer and 1.8897 for the substrate at 632 nm [9]. Similar measurements were made in TM polarization at 972 nm and the values obtained for the refractive indexes were 1.8632 for the layer and 1.8573 for the substrate, measured in this study.…”

“…In order to avoid the difficulties of growing bulk (Yb,Nb):RTP crystals, which are often of low quality [9], and to increase the optical path, (Yb,Nb):RTP planar waveguides were grown on RTP substrates by the liquid phase epitaxy (LPE) method [10]. In these samples efficient type II SHG has already been reported [11].…”

Single-mode rib waveguides in (Yb,Nb) : RbTiOPO4by reactive ion etching

“…(Yb,Nb):RTP gain media can be grown in a waveguide geometry by liquid phase epitaxy (LPE) [5] and planar waveguides with losses lower than 1 dB/cm have been demonstrated. Fabrication of channel waveguides based on this thin-film growth technology is motivated by noting recent work on ion-exchanged glass waveguides [6], showing that Yb 3+ -doped channel waveguides are of interest as compact ultrafast sources with multi-GHz repetition rates, and consequently have potential application in areas such as optical sampling [7], metrology [8] and biological imaging [9].…”

On the reactive ion etching of RbTiOPO<inf>4</inf>

“…In particular, Yb 3+ -doped RTP exhibits a broad fluorescence spectrum that has been exploited to demonstrate ultrafast operation, with pulses as short as 155 fs being generated [1]. Recently, planar waveguiding has been demonstrated in an (Yb 3+ , Nb 5+ ):RTP film grown by liquid phase epitaxy [2], opening the possibility of planar integrated devices based on this highly functional material.…”