David de Felipe

Power-Efficient Thermo-Optic Tunable Filters Based on Polymeric Waveguide Bragg Gratings

Tunable polymer Bragg grating filters with extremely high tuning efficiency are demonstrated. A buried heating scheme is used to achieve fairly uniform heating conditions in the polymer waveguide. Thermal simulation results indicate that the temperature change per unit heating power at the core of the waveguide can be significantly increased by implementing sufficient thermal buffers around it. Simulated and experimental results are in very good agreement. Tuning efficiency has been improved to a record 425 nm/W, corresponding to a tuning power of 88 mW for a wavelength tuning range of close to 40 nm.

Thermally optimized variable optical attenuators on a polymer platform

Variable optical attenuators based on a 1×1 multimode interference device (MMI) and a Mach–Zehnder interferometer (MZI) have been designed, fabricated, and characterized. Thermo-optic simulations have been performed to find the optimal heater electrode layout in order to improve the heating efficiency, suppress thermal crosstalk, and enhance the dynamic attenuation range. Both types of attenuators feature low optical loss (<0.7u2009u2009dB). The compact 1×1 MMI provides a dynamic attenuation range of 35xa0dB over the C band at 10.1xa0mW heater power, while the MZI increases the dynamic range beyond 50xa0dB at merely 1.8xa0mW heater power.

Graphene-based electro-absorption modulator integrated in a passive polymer waveguide platform

A graphene-based electro-absorption modulator has been integrated into a passive polymer waveguide platform for the first time. The opto-electronic properties of the structure are investigated with numerical simulations and measurements of a fabricated device. The graphene layers transferred to the polymer substrate were analyzed by means of Raman spectroscopy and the results indicate a high crystalline quality of the two-dimensional material. The voltage-dependent transmission through a 25 µm long device has been measured in the telecommunications-relevant wavelength range between 1500 nm and 1600 nm yielding an extinction ratio of 0.056 dB/µm.

Hybrid InP-polymer 30 nm tunable DBR laser for 10 Gbit/s direct modulation in the C-Band

A C-Band hybrid InP-polymer tunable DBR laser for direct modulation is presented. The DBR tunes 34 nm with output powers larger 8 mW and SMSRs above 40 dB. 10 Gbit/s operation shows open eye diagrams.

Switchable dual-polarization external cavity tunable laser

An external cavity laser is demonstrated based on the hybrid integration of an InP-based gain element, a half-wave plate, and thermally drivable polymer waveguide circuits. The laser has one oscillation region but two outputs for TE and TM emissions. The central wavelength can be tuned 20 nm at 20 mW heater electrical power. The TM path undergoes a 1.4 dB power penalty due to the presence of the half-wave plate. However, the on-chip thermo-optic switch (TOS) can compensate for this imbalance and steer the laser into an equal TE and TM output power. The TOS can also be adjusted to prefer one polarization path over the other with ∼10u2009u2009dB extinction ratio.

Progress in polymer-based components for next-generation PON applications

Polymer components for next-generation WDM PON are presented, incl. 8ch OLT-Tx and OLT-Rx devices using polymer AWGs and InP-based DFB laser and photo diode arrays together with a 40nm wide tunable InP/polymer Bragg grating laser for realizing colorless ONUs.

Bi-directional, crosstalk-suppressed, 40-nm wavelength tuneable colourless ONU on polymer platform

Colourless ONU is demonstrated on polymer hybrid integration platform. Polymer Bragg gratings provide power-efficient wavelength tuning. C/L band thin-film filter (de)multiplexes the wavelengths. On-chip U-groove offers submount-free fibre attachment. 10 Gb/s bi-directional transmission and detection are achieved.

Photonic integrated devices and functions on hybrid polymer platform

Photonic devices and new functions based on HHI’s hybrid integration platform PolyBoard are presented providing lowloss thin-film-element-based light routing, an on-chip micro-optical bench and flexible chips comprising optical and electrical waveguides. The newly developed transfer and integration of graphene layers enables the fabrication of active optoelectronic devices in the intrinsically passive polymer waveguide networks with bandwidths in the GHz range. These novel functionalities in combination with the mature thermo-optic components of the PolyBoard platform such as tunable lasers, switches and variable attenuators pave the way towards new applications of photonic integrated circuits in communications and sensors.

Recent Developments in Polymer-Based Photonic Components for Disruptive Capacity Upgrade in Data Centers

Recently developed photonic components for next-generation datacenter systems based on the Heinrich Hertz Institute´s PolyBoard integration platform are reviewed. Hybrid-integrated transmitters and receivers, including optical functionalities, such as tunable lasers, polarization manipulators, 1 × 2 switches, and variable optical attenuators, are presented. The flexibility of those devices provides the possibility of generating, routing and detecting multiple optical data flows, offering the potential of aggregating traffics of 1 Tb/s and beyond. In addition, vertically stacked polymer waveguide structures are presented, opening the way towards the third dimension in photonic integration and allowing increasing the transmission capacity beyond the physical limit of standard single mode fibers. The freedom in the arrangement of the polymer waveguides allow for the matching of different multicore fiber types, providing the possibility of processing in parallel the different optical flows. By means of micromachining 45

Temperature-Tolerant Wavelength-Setting and -Stabilization in a Polymer-Based Tunable DBR Laser

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