Optimization of Low-Loss AL2O3AL_{2}O_{3} Waveguide Fabrication for Application in Active Integrated Optical Devices

In this paper we will present the fabrication and properties of reactively co-sputtered $AL_{2}O_{3}$ layers, being a very promising host material for active integrated optics applications such as rare-earth ion doped laser devices. The process optimization towards a reactive co-sputtering process, which resulted in stable, target condition-independent deposition of $AL_{2}O_{3}$ with high optical quality will be discussed in detail. The loss value of as-deposited optical waveguides sputtered by the optimized process has been measured. The loss in the near infrared wavelength range was 0.3 dB/cm. Furthermore $AL_{2}O_{3}$ material hosts fabricated by sputtering techniques are compatible with Si-based integrated optical technology and allow for uniform deposition over a large substrate area

An elastomeric grating coupler

We report on a novel nondestructive and reversible method for coupling free space light to planar optical waveguides. In this method, an elastomeric grating is used to produce an effective refractive index modulation on the surface of the optical waveguide. The external elastomeric grating binds to the surface of the waveguide with van der Waals forces and makes conformal contact without any applied pressure. As a demonstration of the feasibility of the approach, we use it to measure the refractive index of a silicon oxynitride film. This technique is nondestructive, reversible, low cost and can easily be applied to the characterization of optical materials for integrated optics

Presence of fast quenching mechanisms in Al2O3:Er3+

The measurement of luminescence decay curves and non-saturable absorption in erbium-doped aluminum oxide waveguides reveals the presence of fast quenching effects, leading to a revised value of the microscopic and macroscopic parameters of energy-transfer upconversion

Nd-doped aluminum oxide integrated amplifiers at 880 nm, 1060 nm, and 1330 nm

Neodymium-doped Al2O3 layers were deposited on thermally oxidized Si substrates and channel waveguides were patterned using reactive-ion etching. Internal net gain on the Nd3+ transitions at 880, 1064, and 1330 nm was investigated,\ud yielding a maximum gain of 6.3 dB/cm at 1064 nm. Values for the energy-transfer upconversion parameter for different Nd3+\ud concentrations were deduced