Laser operation of Yb^3+ in the acentric RbTiOPO_4 codoped with Nb^5+

Abstract

We report on continuous-wave lasing of Yb(3+) at room temperature in the noncentrosymmetric RbTiOPO(4) crystal, codoped with Nb(5+), for all three possible polarizations. A maximum output power of 154 mW at 1050 nm was obtained for an absorbed power of 386 mW. The highest slope efficiency reached approximately 60% and the lowest threshold (with respect to the absorbed power) was 18 mW. The laser was tunable from 1009 to 1081 nm.

Ar^+ ion milling rib waveguides on nonlinear optical (Yb,Nb):RTP/RTP epitaxial layers

“…This wavelength has been selected because, in previous works, it has been used to pump (Yb,Nb):RTP lasers [7]. The refractive indices of the epitaxial layer and the substrate used in the simulation were measured experimentally via the dark mode method, using a Metricon prism-coupler setup and a Ti:sapphire laser.…”

“…Crystals of this family have been extensively used for frequency doubling infra-red (IR) laser radiation close to 1 µm, such as Yb 3+ and Nd 3+ laser emissions [2,3]. RTP has similar nonlinear optical coefficients to KTP [4], but unlike KTP, it can be doped with Yb 3+ ions to a high enough concentration to allow efficient laser action [5][6][7]. Therefore, by combining the emission of Yb 3+ with the nonlinear optical properties of the crystal, it is possible to obtain a selffrequency doubling material.…”

“…The quantum defect, which leads to the thermal loading of the crystal during the laser operation, is very small in Yb 3+ due to the similarity between the pumping and the laser wavelengths [12]. Moreover, the Yb 3+ ion has no absorption losses at the second-harmonic generation frequency [7], which makes it interesting for self-frequency doubling.…”

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

“…The codoping of RTP with Yb and Nb significantly increases the distribution coefficient of Yb in RTP [7]. Thus, the content of Yb in RTP was high enough to successfully obtain laser emission in these crystals [8].…”

“…On the other hand, the similarity between the pumping and the laser wavelength means that there is a small quantum defect that reduces the thermal loading of the crystals during laser operation [5]. Yb also has no absorption losses at the second harmonic generation (SHG) frequency, which makes it particularly suitable for SFD [6].…”