Porous - silicon microcavities ( * )

Narrow-line light emission from porous silicon multilayers and microcavities

Porous silicon multilayers and microcavities, prepared by the pulsed electrochemical etching method, exhibit a variety of reflectivity and photoluminescence spectra. A comparison of the measured results with those calculated based on the transfer matrix method and quantum-box model reveals that the variation of the spectra can be attributed to the change in wavelength position of the stop-band ...

On the Route towards Efficient Light Emitting Diodes Based on Porous Silicon

In this paper we present our recent progresses towards effkient light emitting diodes based on porous silicon. We will touch the two following topics: 1) All porous silicon microcavities. Through the formation of a planar optical cavity it is possible to vary the spontaneous emission rate of porous silicon films. We demonstrate this by showing luminescence, and time resolved luminescence measur...

Electrical and thermal modulation of silicon photonic bandgap microcavities containing liquid crystals.

Electrical and thermal modulation of porous silicon microcavities is demonstrated based on a change in the refractive index of liquid crystals infiltrated in the porous silicon matrix. Positive and negative anisotropy liquid crystals are investigated, leading to controllable tuning to both longer and shorter wavelengths. Extinction ratios greater than 10 dB have been demonstrated. Larger attenu...

Enhancement of the blue photoluminescence intensity for the porous silicon with HfO2 filling into microcavities

With HfO2 filled into the microcavities of the porous single-crystal silicon, the blue photoluminescence was greatly enhanced at room temperature. On one hand, HfO2 contributes to the light emission with the transitions of the defect levels for oxygen vacancy. On the other hand, the special filling-into-microcavities structure of HfO2 leads to the presence of ferroelectricity, which greatly enh...

Porous silicon microcavities: synthesis, characterization, and application to photonic barcode devices

We have recently developed a new type of porous silicon we name as porous silicon colloids. They consist of almost perfect spherical silicon nanoparticles with a very smooth surface, able to scatter (and also trap) light very efficiently in a large-span frequency range. Porous silicon colloids have unique properties because of the following: (a) they behave as optical microcavities with a high ...

Optical properties of erbium-implanted porous silicon microcavities