Erbium-doped Silicon-rich Oxide Research Articles

Energy transfer from luminescent centers to Er3+ in erbium-doped silicon-rich oxide films

The energy transfer mechanism between luminescent centers (LCs) and Er3+ in erbium-doped silicon-rich oxide (SROEr) films prepared by electron beam evaporation is investigated. Intense photoluminescence of the LCs (weak oxygen bonds, neutral oxygen vacancies, and Si=O states) within the active matrixes is obtained. Fast energy transfer from Si=O states to Er3+ takes advantage in the SROEr film and enhances the light emission from Er3+. The introduction of Si nanoclusters, which induces the Si=O states and facilitates the photon absorption of the Si=O states, is essential to obtain intense photoluminescence from both Si=O states and Er3+.

The modulation on luminescence of Er3+-doped silicon-rich oxide films by the structure evolution of silicon nanoclusters

A series of silicon-rich oxide (SRO) and erbium-doped SRO (SROEr) films imbedded with structural tunable silicon nanoclusters (Si NCs) have been fabricated using sputtering followed by post-annealing. The coalescence of Si NCs is found in the films with large Si excess. The energy transfer rate between Si NCs and Er3+ is enhanced, but the luminescence efficiencies of both Si NCs and Er3+ are reduced by the coalescent microstructures. Optimization of the microstructures of Si NCs is performed, and the preferential optical performance for both Si NCs and Er3+ could be achieved when Si NCs were separated in microstructures.

Erbium-Doped Silicon-Rich Oxide Waveguides Fabricated by Using an Electro-Chemical Method

In this article, we describe and electro-chemical method for fabricating erbium-doped silicon-rich oxide (SRO) waveguides. The porosity, the Er-ion concentration and the refractive index can be controlled by varying the current density (continuous or pulsed currents) during the production process. The refractive index di erence between the core and the cladding layers and the pro le of the SRO waveguides were tested by using an m-line spectrometer and Field-emission scanning electron microscope (FE-SEM). The photo-luminescent (PL) emission of Er-ions at 1550 nm in the SRO waveguides could be obtained even when the excitation wavelength was away from the resonance absorption band of the Er-ions. This result revealed that Er-ions are possibly excited from the ground state I15=2 to the rst excited state I13=2 by energy transfer from excited Si nanocrystallites. The Er-doped SRO waveguides can be applied to optoelectronic devices compatible with Si-based integrated circuit technology.

Whispering gallery modes in Er-doped silicon-rich oxide toroidal microcavities on chip

We report the fabrication process of ultrahigh- Q toroidal microcavities (10–50 μm diameter) and integration of erbium-doped silicon-rich oxide thin film inside these structures. The microcavities are studied by micro-photoluminescence and show the presence of whispering gallery modes at room temperature. Quality factors as high as 3000 are measured, limited by the setup resolution.

Efficient coupling of Er-doped silicon-rich oxide to microdisk whispering gallery modes

We report room-temperature light emission from erbium-doped silicon-rich oxide integrated in a silica microdisk. Silica disks are fabricated by standard optical lithography and etching techniques. Erbium-doped silicon-rich oxide is then deposited by coevaporation of silicon and erbium under oxygen flux. A spatially resolved photoluminescence experiment highlights the efficient coupling of the signal to whispering gallery modes when the excitation beam is focused near the edge of the disk. Quality factors as high as 3000 are measured, limited by the setup’s spectral resolution.