Toward a 1.54 $\mu$m Electrically Driven Erbium-Doped Silicon Slot Waveguide and Optical Amplifier (original) (raw)

Opto-electrical characterization of erbium-doped slot waveguides

Silicon Photonics and Photonic Integrated Circuits III, 2012

The convergence of photonics and microelectronics within a single chip is still lacking of a monolithical on-chip optical amplifier. Rare-earth doped slot waveguides show a large potential as on-chip source. Slot waveguides with silicon nanocrystals embedded in a dielectric host matrix can increase the light confinement in the active layer and allow electrical injection. In this work, horizontal slot waveguides formed by two thick silicon layers separated by a thin erbium doped silicon rich silicon oxide layer are studied as on-chip optical amplifiers. The waveguides are grown in a CMOS line with the active material grown by low-pressure chemical vapor deposition. Optical tests are performed and light propagation in the slot waveguides is observed. Using the cut-back technique, spectra propagation losses are evaluated. Room temperature electroluminescence is observed at 1.54 µm. Transmitted optical signal resonant with Er absorption is studied as a function of the injected current for different probing laser wavelengths.

Electrical pump & probe and injected carrier losses quantification in Er doped Si slot waveguides

2012

Electrically driven Er 3+ doped Si slot waveguides emitting at 1530 nm are demonstrated. Two different Er 3+ doped active layers were fabricated in the slot region: a pure SiO 2 and a Si-rich oxide. Pulsed polarization driving of the waveguides was used to characterize the time response of the electroluminescence (EL) and of the signal probe transmission in 1 mm long waveguides. Injected carrier absorption losses modulate the EL signal and, since the carrier lifetime is much smaller than that of Er 3+ ions, a sharp EL peak was observed when the polarization was switched off. A time-resolved electrical pump & probe measurement in combination with lock-in amplifier techniques allowed to quantify the injected carrier absorption losses. We found an extinction ratio of 6 dB, passive propagation losses of about 4 dB/mm, and a spectral bandwidth > 25 nm at an effective d.c. power consumption of 120 μW. All these performances suggest the usage of these devices as electro-optical modulators.

Electrically pumped Er-doped light emitting slot waveguides for on-chip optical routing at 1.54 μm

Proceedings of SPIE - The International Society for Optical Engineering, 2013

Optoelectronic properties of Er 3+ -doped slot waveguides electrically driven are presented. The active waveguides have been coupled to a Si photonic circuit for the on-chip distribution of the electroluminescence (EL) signal at 1.54 μm. The Si photonic circuit was composed by an adiabatic taper, a bus waveguide and a grating coupler for vertical light extraction. The EL intensity at 1.54 μm was detected and successfully guided throughout the Si photonic circuit. Different waveguide lengths were studied, finding no dependence between the waveguide length and the EL signal due to the high propagation losses measured. In addition, carrier injection losses have been observed and quantified by means of time-resolved measurements, obtaining variable optical attenuation of the probe signal as a function of the applied voltage in the waveguide electrodes. An electro-optical modulator could be envisaged if taking advantage of the carrier recombination time, as it is much faster than the Er emission lifetime. Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/07/2013 Terms of Use: http://spiedl.org/terms Proc. of SPIE Vol. 8767 87670I-6 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/07/2013 Terms of Use: http://spiedl.org/terms

Broadband enhancement of light emission in silicon slot waveguides

Optics Express, 2009

We investigate the light emission properties of electrical dipole emitters inside 2-dimensional (2D) and 3-dimensional (3D) silicon slot waveguides and evaluate the spontaneous emission enhancement (F p ) and waveguide coupling ratio (β). Under realistic conditions, we find that greater than 10-fold enhancement in F p can be achieved, together with a β as large as 0.95. In contrast to the case of high Q optical resonators, such performance enhancements are obtained over a broad wavelength region, which can cover the entire emission spectrum of popular optical dopants such as Er. The enhanced luminescence efficiency and the strong coupling into a limited set of well-defined waveguide modes enables a new class of power-efficient, CMOS-compatible, waveguide-based light sources.

Direct evidence of light confinement and emission enhancement in active silicon-on-insulator slot waveguides

Applied Physics Letters, 2006

The authors experimentally demonstrate strong light confinement and enhancement of emission at 1.54 m in planar silicon-on-insulator waveguides containing a thin layer ͑slot͒ of SiO 2 with Er 3+ doped Si nanoclusters. Angle-resolved attenuated total reflectance is used to excite the slab guided modes, giving a direct evidence of the strong confinement of the electric field in the low-index active material for the fundamental transverse-magnetic mode. By measuring the guided photoluminescence from the cleaved-edge of the sample, the authors observe a more than fivefold enhancement of emission for the transverse-magnetic mode over the transverse-electric one. These results show that Si-based slot waveguides could be important as starting templates for the realization of Si-compatible active optical devices.

Fully Integrated Silicon Photonic Erbium-Doped Nanodiode for Few Photon Emission at Telecom Wavelengths

Materials

Recent advancements in quantum key distribution (QKD) protocols opened the chance to exploit nonlaser sources for their implementation. A possible solution might consist in erbium-doped light emitting diodes (LEDs), which are able to produce photons in the third communication window, with a wavelength around 1550 nm. Here, we present silicon LEDs based on the electroluminescence of Er:O complexes in Si. Such sources are fabricated with a fully-compatible CMOS process on a 220 nm-thick silicon-on-insulator (SOI) wafer, the common standard in silicon photonics. The implantation depth is tuned to match the center of the silicon layer. The erbium and oxygen co-doping ratio is tuned to optimize the electroluminescence signal. We fabricate a batch of Er:O diodes with surface areas ranging from 1 µm × 1 µm to 50 µm × 50 µm emitting 1550 nm photons at room temperature. We demonstrate emission rates around 5 × 106 photons/s for a 1 µm × 1 µm device at room temperature using superconducting n...

Fabrication and optical properties of erbium-doped silicon-rich oxide planar waveguides

2008

In this article we describe the electrochemical method for fabricating Erbium-doped silicon-rich oxide (SRO) planar waveguides. The porosity, Er-ion concentration and the refractive index can be controlled by varying the current density (continuous or pulse currents) during the production process. The refractive index difference between the core and the cladding layers and the profile of SRO waveguides tested by m-line spectrometer and by FE-SEM. The photo-luminescent (PL) emission of Er-ions at 1550 nm in the SRO waveguides can be obtained even when the excitation wavelength was away from resonance absorption band of Er-ions. This result revealed that the observed emission at 1550 nm is possible due to the energy transfer from excitons confined in the nc-Si to Er-ions. The Er-doped SRO waveguides can be applied to optoelectronic devices compatible to Si-based integrated circuit technology.

1.54 μm Er3+ photoluminescent and waveguiding properties of erbium-doped silicon-rich silicon oxide

Journal of Applied Physics, 2000

1.54 μm Er3+ photoluminescent and waveguiding properties of erbium-doped silicon-rich silicon oxide (SRSO) are investigated. Optimum Er3+ luminescence was obtained after an anneal of at least 5 min at 950 °C, and at least 1 at. % excess silicon in SRSO was necessary for the excitation of erbium to be dominated by carriers. The refractive index and the bulk waveguide loss of erbium-doped SRSO film with 0.1 at. % erbium and 1 at. % excess silicon after the optimal anneal treatment was 1.4817 and 4.0 dB/cm, respectively. Fabrication of an erbium-doped SRSO strip waveguide using the standard Si processing techniques and the guiding of internal 1.54 μm Er3+ emission by such a strip waveguide are demonstrated.

Erbium implanted silicon rich oxide thin films suitable for slot waveguides applications

Optical Materials, 2011

Thin (50 nm) erbium implanted silicon rich oxide films suitable for slot waveguides applications have been produced and studied by means of optical spectroscopy and structural characterisation techniques. Comparison between different deposition techniques in terms of light emitting properties of erbium ions is presented. Special attention is given to the efficiency improvement of the energy transfer from silicon nanoclusters to erbium ions where the type of annealing treatment is proven to be of crucial importance.