Laser-induced forward transfer techniques for printing functional materials and photonic devices

The subject of this thesis is to study the Laser-Induced Forward Transfer (LIFT) tech-nique using a time-resolved method in order to gain a better insight into the dynamics of the transfer process and to use the technique for rapid prototyping of photonic devices and printing piezoelectric materials for energy harvesting applications. A nanosecond shadowgraphy technique was used to study the triazene polymer (TP)-dynamic release layer (DRL) assisted LIFT technique for solid-phase ceramic materials namely gadolinium gallium oxide (Gd-Ga-O)and ytterbium doped yttrium aluminium oxide (Yb:YAG). The dependence of the distance travelled by the shockwave and the ejected donor material, their velocities and the quality of the ejected donor pixel on the laser fluence, the thickness of the TP-DRL and donor film thickness was studied and is discussed. Segmented channel waveguides, X-couplers and mode-filters based on titanium (Ti) in-diffused lithium niobate (LN) have been fabricated using the LIFT technique. The segment separation was found to be the key factor in determining mode profiles of waveguides. The corrugations due to the segmented nature of the deposits was observed to introduce non-adiabatic behavior in the mode filters which was further confrmed by theoretical modeling. Forward transfer of donor films with patterns to be transferred machined into them prior to LIFT have been investigated. This technique allows debris-free printing of thicker and fragile donors films with extremely smooth and uniform edges in intact and solid-phase without the need of any sacrificial layer. Results of debris-free printing of micro-pellets of zinc oxide (ZnO) with extremely good quality edges from donor films pre-machined using focused ion beam (FIB) are presented. Printing and post-transfer characterization of both lead zirconate titanate (PZT) and non-lead based ZnO piezoelectric materials for energy harvesting applications using the LIFT and TP-DRL assisted LIFT techniques have been studied and discussedEThOS - Electronic Theses Online ServiceGBUnited Kingdo

12.5GB operation of a novel monolithic 1.55µm BPSK source based on prefixed optical phase switching

Novel optical phase switching BPSK transmitter was used to transmit 12.5GB signal over 40km. Speed scalability, ultra-small footprint and low power drive of the monolithic circuit are attractive for advanced format migration towards low-cost applications

12.5GB operation of a novel monolithic 1.55µm BPSK source based on prefixed optical phase switching

Novel optical phase switching BPSK transmitter was used to transmit 12.5GB signal over 40km. Speed scalability, ultra-small footprint and low power drive of the monolithic circuit are attractive for advanced format migration towards low-cost applications

Giant linewidth enhancement factor and purely frequency modulated emission from quantum dot laser

Giant effective linewidth enhancement factors, close to 60, are measured on a quantum dot laser under specific biasing conditions. Consequently, 2.5 Gbit/s purely frequency modulated signal is obtained by direct current modulation at this operation point

Giant linewidth enhancement factor and purely frequency modulated emission from quantum dot laser

Giant effective linewidth enhancement factors, close to 60, are measured on a quantum dot laser under specific biasing conditions. Consequently, 2.5 Gbit/s purely frequency modulated signal is obtained by direct current modulation at this operation point

64Gb/s electro absorption modulator operation in InP-based active-passive generic integration platform

We have designed, fabricated and characterized an electro-absorption modulator integrated with generic technology on a semi-insulating substrate. The modulator operates at 64Gb/s with 6dB dynamic extinction ratio, a bias voltage of -2.2V and a voltage swing of 3.5V

High speed and high responsivity UTC photodiode module for >40 Gb/s optical receivers

International audienc

The Dual-Electroabsorption Modulated Laser, a Flexible Solution for Amplified and Dispersion Uncompensated Networks Over Standard Fiber

International audienceWe propose here a monolithically integrated dual RF access electroabsorption-modulated laser called D-EML for the generation of optical single-sideband signal for both nonreturn to zero and orthogonal frequency division multiplexing formats. The benefits of optical single-sideband over double sideband in terms of resilience against chromatic dispersion effects are presented for high-bit rate intensity modulation/direct detection transmissions over standard single mode fiber in the C-band. Both simulation and experimentation exhibit transmission distance enhancement in the case of dual modulation of the D-EML, i.e., in optical single-sideband configuration, making this optical source an interesting solution because of its low-cost, low-size, and reasonable-power consumption

Optical feedback tolerance of quantum dot and quantum dash based semiconductor lasers operating at 1.55µm

International audienceThis paper reports on the tolerance of low-dimensional InAs/InP quantum-dash- and quantum-dot-based semiconductor lasers to optical feedback in the 1.55 mum window. For this purpose, the onset of coherence collapse (CC) is experimentally determined and systematically investigated as a function of different laser parameters, such as the injection current, differential gain, temperature, and photon lifetime. It is in particular found that for both material systems the onset of CC increases with the injection current in a similar way to bulk or quantum-well-based devices. Of most importance, we experimentally show that the differential gain plays a key role in the optical feedback tolerance. It is indeed shown to determine not only the range of the onset of CC but also the dependence of this threshold both on the temperature and laser cavity length. Increasing the operating temperature from 25degC to 85degC leads to a decrease of the onset of CC by a factor of only ~3 dB, well accounted for by the variation of the differential gain in this temperature range. We find no difference in the tolerance to external reflections of a truly 3-D confined quantum-dot-based laser and a quantum dash device of the same cavity length, which have similar differential gains. A tentative analysis of our data is finally carried out, based on existing models