100 GHz Multiple Colliding Pulse Generation from Cleaved Facet-free Multi-section Semiconductor Laser Diode
Jessica Cesar Cuello1, Robinson Guzman1, Alberto Zarzuelo1, Mu Chieh Lo1, Muhsin Ali1, Guillermo
1 University Carlos III of Madrid, UC3M, Electronics Technology Department
A monolithically integrated semiconductor laser with a cavity laser of a 25 GHz fundamental repetition rate has been designed to generate an optical signal of four-times of the fundamental repetition rate working on the fourth harmonic colliding pulse mode locking configuration. This device was developed and fabricated within a multi-project wafer run in an InP-based active-passive generic foundry. The Fabry-Pérot laser cavity structure of the semiconductor laser is formed with two on-chip reflector building blocks rather than cleaved facets of the chip.
The Fabry-Perot laser cavity length is around 1.66 mm the cavity three absorber sections symmetrically divide the cavity into four gain segments. An electrical linewidth of 350 KHz and 150 KHz with a frequency spacing of 25 GHz y 100 GHz is generated by the laser in passive regimen condition, respectively.
Keywords: semiconductor laser, electrical linewidth, multiple colliding pulse, mode locking laser
Experimental Characterization of a Novel Energy-efficient Integrated Microwave Photonics Modulator
Iterio Degli-Eredi and Martijn J. R. Heck
Aarhus Universitet – Department of Engineering, Finlandsgade 22, 8200 Aarhus, Denmark
We design and experimentally characterize a novel microwave (MW) photonics ring modulator based on waveguide-resonator coupling modulation. The experiments reveal that at MW frequencies corresponding to the FSR of the ring or integer multiples thereof, the resonant device generates 10 to 19 times higher MW output power than the equivalent standard Mach-Zehnder modulator, thus showing our resonant modulator paves the way for energy-efficient and low driving MW power operation. Moreover, as this resonant enhancement occurs
over a bandwidth of 2 to 3 GHz, our modulator has the potential to be implemented as a key element in the upcoming microwave and millimeter wave bands of 5G networks. Finally, the device solely consists of standard
building blocks provided by the multi-project wafer run of the SMART Photonics foundry, thus showing it can be fabricated in a relatively mature photonics integration process.
Keywords: Microwave Modulators, Ring Resonators, Indium Phosphide, Microwave Photonics, Integrated Microwave Photonics
Waveguide Photonic Crystal Reflectors on InP-Membranes-on-Silicon
Sander Reniers 1, Jorn van Engelen 1, Kevin Williams 1, Jos van der Tol 1, Yuqing Jiao 1
1Photonic Integration Group, Institute for Photonic Integration, Eindhoven University of Technology,
PO Box 513, 5600 MB Eindhoven, The Netherlands
We present waveguide photonic crystal reflectors on an InP-membrane-on-silicon (IMOS). Photonic crystal holes are patterned on a waveguide using electron-beam lithography to create a broadband distributed Bragg reflector. We show simulations of these reflectors and experimental results of fabricated devices, both showing a high, free to choose reflectivity, and high quality factor Fabry-P´erot cavities. We experimentally show reflectivities >90% for the reflectors and a quality factor as high as 11,4301,446 for a Fabry-P´erot cavity,
using reflectors with a length of only 4 microns.
Keywords: photonic integrated circuits, photonic membrane, photonic crystal, waveguide reflector.
Low-Voltage InP MEMS Optical Switch on Silicon
Tianran Liu1, Francesco Pagliano1, 2, René van Veldhoven1, Vadim Pogoretskii1, Yuqing Jiao1,
1Department of Applied Physics and Institute for Photonic Integration,
Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven, The Netherlands
2nanoPHAB, Groene Loper 19, Postbus 513, Eindhoven 5612 AP, The Netherlands
In this paper, a novel MEMS Mach-Zehnder interferometer optical switch is presented. Switching is achieved by tuning the vertical gap between two coupled waveguides through the application of a reverse bias on a p-i-n junction. The switching requires a voltage as low as 4.4V and provides an extinction ratio above 15dB within a 34 nm bandwidth in the C-band. The device also serves as a very efficient optical phase modulator, being able to modify the optical phase by more than 4π with only 6.5V voltage in a 140μm-long waveguide. Our work provides a solution to on-chip optical switching for low-voltage applications. The switch is fabricated on an indium-phosphide membrane on a silicon substrate, which enables the integration with active components (e.g. amplifiers, lasers, detectors) on a single chip.
Keywords: Optical switch, MEMS, phase modulator, Mach-Zehnder interferometer, Indium-phosphide.