A5072894894- solar cell performance optimization
- Chalcogenide Semiconductor Thin Films
- Semiconductor Quantum Structures and Devices
- Silicon and Solar Cell Technologies
- Nanowire Synthesis and Applications
- Thin-Film Transistor Technologies
- Thermal Radiation and Cooling Technologies
- Semiconductor materials and interfaces
- Photovoltaic System Optimization Techniques
- Quantum Dots Synthesis And Properties
- Particle accelerators and beam dynamics
- Magnetic confinement fusion research
- Electron and X-Ray Spectroscopy Techniques
- Semiconductor materials and devices
- Perovskite Materials and Applications
- Advanced Semiconductor Detectors and Materials
- Solar Thermal and Photovoltaic Systems
- GaN-based semiconductor devices and materials
- Superconducting Materials and Applications
- Semiconductor Lasers and Optical Devices
- Photonic and Optical Devices
- Advanced Thermodynamics and Statistical Mechanics
- Silicon Nanostructures and Photoluminescence
- Solar Radiation and Photovoltaics
- Energy Harvesting in Wireless Networks
Hospital Universitario La Paz
2025
Plasma Technology (United States)
2024-2025
Massachusetts Institute of Technology
2024-2025
Fusion Academy
2024-2025
Fusion (United States)
2024-2025
Universidad Politécnica de Madrid
2015-2024
University of Castilla-La Mancha
2023
IMDEA Energy Institute
2012-2022
Instituto de Aeronáutica e Espaço
2022
ORCID
2020-2021
The self-absorption of radiated photons increases the minority carrier concentration in semiconductor optoelectronic devices such as solar cells. This so-called photon recycling leads to an increase external luminescent efficiency, fraction internally that are able escape through front surface. An increased efficiency turn correlates with open-circuit voltage and ultimately conversion efficiency. We develop a detailed ray-optical model calculates Voc for real, non-idealized cells, accounting...
We demonstrate 1.81 eV GaInP solar cells approaching the Shockley-Queisser limit with 20.8% conversion efficiency, 8% external radiative and 80–90% internal efficiency at one-sun AM1.5 global conditions. Optically enhanced voltage through photon recycling that improves light extraction was achieved using a back metal reflector. This optical enhancement realized currents when non-radiative Sah-Noyce-Shockley junction recombination current reduced by placing of cell in higher band gap AlGaInP...
The emission of light from each junction in a series-connected multijunction solar cell both complicates and elucidates the understanding its performance under arbitrary conditions. Bringing together many recent advances this understanding, we present general 1-D model to describe luminescent coupling that arises voltage-driven electroluminescence voltage-independent photoluminescence nonideal junctions include effects such as Sah-Noyce-Shockley (SNS) recombination with n ≠ 2, Auger...
We present results for quadruple-junction inverted metamorphic (4J-IMM) devices under the concentrated direct spectrum and analyze limitations to performance. The integrate lattice-matched subcells with rear heterojunctions, as well lattice-mismatched low threading dislocation density. To interconnect subcells, thermally stable tunnel junctions are used, a GaAsSb/GaInAs junction between subcells. A broadband antireflection coating is front metal grid designed high concentration operation....
The inverted metamorphic solar cell has highly tunable bandgaps, in part due to the subcells. Using phosphide-based compositionally graded buffers, we show a wide variety of GaInAs cells, ranging bandgap from 1.2 0.7 eV. These subcells are all high quality and can be used for multijunction designs. cells with 0.70 eV bandgaps developed using an InAsP buffer that extends beyond InP lattice constant, allowing access additional 2 mA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...
For solar cells dominated by radiative recombination, the performance can be significantly enhanced improving internal optics. We demonstrate a detailed model for that calculates external luminescent efficiency and discuss relationship between luminescence. The accounts wavelength-dependent optical properties in each layer, parasitic electrical losses, multiple reflections within cell, assumes isotropic emission. single-junction cells, calculation leads to V <sub...
A three-dimensional (3-D) distributed model for high-concentrator solar cells based on elementary units made up of electrical circuits is presented. The recombination mechanisms are dealt with in detail, paying special attention to the perimeter properties. No ohmic effect omitted making this a powerful simulation tool concentrator cells. shunt resistance also included. allows external connections and nonuniform illumination profiles very useful optimizing future structures technological...
Photovoltaic conversion efficiencies of 32.6% and 30% at concentrations 1000 3500 suns, respectively, are achieved in monolithic GaInP/GaAs dual-junction solar cells grown lattice matched on a GaAs substrate by metal-organic vapor-phase epitaxy. The tunnel-junction design, based an (Al)GaAs/GaAs heterojunction, is found to be key factor for achieving this efficiency such high concentrations. Moreover, the thorough design joint optimization front grid top-cell emitter, using...
Abstract This paper studies the recombination at perimeter in subcells that constitute a GaInP/GaAs/Ge lattice‐matched triple‐junction solar cell. For that, diodes of different sizes and consequently perimeter/area ratios have been manufactured single‐junction cells resembling It has found neither GaInP nor Ge is significant devices as small 500 μ m × m(2.5 ⋅ 10 − 3 cm 2 ) 250 (6.25 4 Ge. However, GaAs, not negligible low voltages even large 1cm , it main limiting factor open circuit voltage...
Abstract An n ++ -GaAs/p -AlGaAs tunnel junction with a peak current density of 10 100 A cm −2 is developed. This device for multijunction solar cells, grown lattice-matched on standard GaAs or Ge substrates, the highest ever reported. The voltage drop equivalent to operation cell up 000 suns below 5 mV. Trap-assisted tunnelling proposed be behind this performance, which cannot justified by simple band-to-band tunnelling. metal-organic vapour-phase epitaxy growth conditions, are in limits...
Due to spectral sensitivity effects, using a single standard spectrum leads large uncertainty when estimating the yearly averaged photovoltaic efficiency or energy yield. Here we demonstrate how machine learning techniques can reduce sets by three orders of magnitude few characteristic spectra, and use resulting proxy spectra find optimal solar cell designs maximizing production. When conditions, our calculated limits show good agreement with current records, but cells designed for record...
The main limiting factors of multijunction solar cells operating under ultra-high concentration (>1000 suns) are examined by means 2D physically based numerical modelling. validation the model is carried out fitting calibrated light measurements. Because series resistance most important constraint in electrical performance cell irradiance, it analysed and quantified detailing different contributions such as: (i) properties emitter; (ii) window layer top cell; (iii) band discontinuities...
The quasi-3D models based on distributed circuit units are a powerful tool to analyse the performance of solar cell from point view its electrical behavior. Quite accurate have been developed in past that reproduce experimental data single-junction cells very closely. These help determination origin peculiarities dark and one sun or high concentration I–V curves. They also allow design front grid, analysis impact parameters final device, etc. In this work, these used study effect non-uniform...
The three-junction 1.8/1.4/1.0-eV inverted metamorphic multijunction solar cell can be extended to four junctions by adding another lattice-mismatched GaInAs junction with a bandgap of 0.7 eV. However, this requires significant amount mismatch GaAs substrates, i.e., 3.8%, which is difficult obtain while maintaining high-quality material. In paper, we perform an in-depth investigation GaInP compositionally graded buffer varying in composition between Ga 0.5In 0.5P and InP order identify...
The consideration of real operating conditions for the design and optimization a multijunction solar cell receiver–concentrator assembly is indispensable. Such requirement involves need suitable modeling simulation tools in order to complement experimental work circumvent its well-known burdens restrictions. Three-dimensional distributed models have been demonstrated past be powerful choice analysis phenomena single- dual-junction cells, as well strategies minimize losses when under high...
Abstract Tunnel junctions are key for developing multijunction solar cells (MJSC) ultra‐high concentration applications. We have developed a highly conductive, high bandgap p + ‐AlGaAs/n ‐GaInP tunnel junction with peak tunneling current density as‐grown and thermal annealed devices of 996 A/cm 2 235 , respectively. The J – V characteristics the after annealing, together its behavior at MJSCs typical operation temperatures, indicate that this is suitable candidate concentrator MJSC designs....
Multijunction solar cells can be fabricated by mechanically bonding together component that are grown separately. Here, we present four-junction four-terminal mechanical stacks composed of GaInP/GaAs tandems on GaAs substrates and GaInAsP/GaInAs InP substrates. The were bonded with a low-index transparent epoxy acts as an angularly selective reflector to the bandedge luminescence, while simultaneously transmitting nearly all subbandgap light. As determined electroluminescence measurements...
Abstract Germanium is listed as a critical raw material, and for environmental economic sustainability reasons, strategies lower consumption must be implemented. A promising approach Ge lift‐off concepts, which enable to re‐use the substrate multiple times. Our concept based on Ge‐on‐Nothing that controlled restructuring at high temperature of macroporous surface, forming foil weakly attached its parent wafer. Its suitability III–V epitaxy seed support has previously been demonstrated with...