A5007061797- solar cell performance optimization
- Semiconductor Quantum Structures and Devices
- Chalcogenide Semiconductor Thin Films
- Advanced Semiconductor Detectors and Materials
- Nanowire Synthesis and Applications
- Advanced Optical Sensing Technologies
- Photovoltaic System Optimization Techniques
- Quantum Dots Synthesis And Properties
- Silicon Carbide Semiconductor Technologies
- Spectroscopy and Quantum Chemical Studies
- Advanced Memory and Neural Computing
- Photonic and Optical Devices
- Semiconductor materials and devices
- Silicon and Solar Cell Technologies
- Neural Networks and Reservoir Computing
- Thin-Film Transistor Technologies
- Solar Thermal and Photovoltaic Systems
- Optical Systems and Laser Technology
Université de Sherbrooke
2015-2019
Centre de Nanosciences et de Nanotechnologies
2016-2017
Optical to electrical power converting semiconductor devices were achieved with breakthrough performance by designing a Vertical Epitaxial Heterostructure Architecture. The are featuring modeled and measured conversion efficiencies greater than 65%. ultrahigh obtained monolithically integrating several thin GaAs photovoltaic junctions tailored submicron absorption thicknesses grown in single crystal epitaxy. heterostructures that engineered number N of such ultrathin yielded an optimal...
As it is getting increasingly difficult to achieve gains in the density and power efficiency of microelectronic computing devices because lithographic techniques reaching fundamental physical limits, new approaches are required maximize benefits distributed sensors, micro-robots or smart materials. Biologically-inspired devices, such as artificial neural networks, can process information with a high level parallelism efficiently solve problems, even when implemented using conventional...
Photovoltaic power converting III–V semiconductor devices based on the Vertical Epitaxial HeteroStructure Architecture (VEHSA) design have been achieved with up to 20 thin p/n junctions (PT20). Open circuit photovoltages in excess of 23 V are measured for a continuous wave monochromatic optical input ∼1 W tuned 750 nm–875 nm wavelength range. Conversion efficiencies greater than 60% demonstrated when PT20 near peak their spectral response. Noticeably, structure is implemented its narrowest...
Photon‐recycling effects are studied experimentally in photovoltaic power converting III–V semiconductor devices designed with the vertical epitaxial heterostructure architecture (VEHSA). The responsivity of VEHSA structures multiple thin GaAs n/p junctions is measured for various optical input powers and different wavelength detuning values respect to peak spectral response. While excitation decreases external quantum efficiency at low powers, this study demonstrates that high intensities,...
This review outlines a series of developments in the design, modelling and growth multi-junction laser power converters, including several observations GaAs monolithic vertical epitaxial heterostructure architecture devices with astonishing mono-chromatic optical to electrical conversion efficiencies 65–70% range. Experimental data is presented for ranging from single up 20 p/n junctions, generally exhibiting weak dependence on source detuning which serves as evidence strong photon recycling...
A monolithic compound semiconductor phototransducer optimized for narrow-band light sources was designed and has achieved conversion efficiencies exceeding 50%. The III-V heterostructure grown by MOCVD, based on the vertical stacking of a number partially absorbing GaAs n/p junctions connected in series with tunnel junctions. thicknesses p-type base layers diodes were engineered optimal absorption current matching an optical input wavelengths centered 830 nm to 850 range. device architecture...
GaAs phototransducers with 5 to 12 p/n junctions are shown demonstrate breakthrough performance in optical conversion efficiency ranging from 65% just under 70%. In particular, for a current-matched junction device we have recorded an of 66.5% at V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">oc</sub> = 14.46V (open circuit voltage) approximately 650 suns / 841 nm monochromatic source. Our simulations reproduce the PV characteristics physical...
PV devices with active areas of ~3:4 mm<sup>2</sup> were fabricated and tested top electrodes having different emitter gridline spacings area shadowing values between 0% 1.8%. As expected, the thicker <i>n/p</i> junctions exhibit hindered photocarrier extraction, low fill factor (FF) values, for prepared sparse designs. However, this study clearly demonstrates that thin extraction can still be efficient (FF > 80%) even no gridlines, which we explain using a TCAD model. The electric field...
Photovoltaic cells are detrimentally impacted by exposure to ionizing radiation, a consideration of particular significance for applications in outer space. In this paper, we demonstrate that vertical epitaxial heterostructure architecture (VEHSA) laser power converters particularly resilient toward radiation-induced degradation; particular, observed reductions efficiency 1.9% and 6.4% 5- 20-junction monolithic devices, respectively, at near 3 W input (V <sub...
Abstract We treat the exciton–thermal acoustic phonon interaction as a coupling to (not necessarily classical) stochastic background, in turn applying Luttinger–Ward style of resummation self–energy diagrams and leading non–perturbative resolution exciton spectral density. Such an approach is useful settings where higher order corrections are not small, e.g. finite temperature certain processes involving optical phonons. Our main observations lend promising outlook for applications with...
We study the constraints on electrical and thermal efficiency of an integrated photovoltaic solar heating system over a large range possible design parameters. These include geometry set-up, concentration ratios, properties materials used (emissivities, conductivities, etc.) flow rates. Our model quantifies relative influence exhibited by each these parameters overall as well exterior surface temperatures. In effect, we are able to assess exclude configurations which anticipated operate at...