Eli Yablonovitch is an American physicist and engineer who, along with Sajeev John, founded the field of photonic crystals in 1987. He and his team were the first to create a 3-dimensional structure that exhibited a full photonic bandgap, which has been named Yablonovite. In addition to pioneering photonic crystals, he was the first to recognize that a strained quantum-well laser has a significantly reduced threshold current compared to its unstrained counterpart. This is now employed in the majority of semiconductor lasers fabricated throughout the world. His seminal paper reporting inhibited spontaneous emission in photonic crystals is among the most highly cited papers in physics and engineering.
Quantum dots (QDs) or semiconductor nanocrystals are semiconductor particles a few nanometres in size with optical and electronic properties that differ from those of larger particles via quantum mechanical effects. They are a central topic in nanotechnology and materials science. When a quantum dot is illuminated by UV light, an electron in the quantum dot can be excited to a state of higher energy. In the case of a semiconducting quantum dot, this process corresponds to the transition of an electron from the valence band to the conductance band. The excited electron can drop back into the valence band releasing its energy as light. This light emission (photoluminescence) is illustrated in the figure on the right. The color of that light depends on the energy difference between the conductance band and the valence band, or the transition between discrete energy states when the band structure is no longer well-defined in QDs.
A quantum well is a potential well with only discrete energy values.
The term quantum efficiency (QE) may apply to incident photon to converted electron (IPCE) ratio of a photosensitive device, or it may refer to the TMR effect of a magnetic tunnel junction.
A solar cell or photovoltaic cell is an electronic device that converts the energy of light directly into electricity by means of the photovoltaic effect. It is a form of photoelectric cell, a device whose electrical characteristics vary when it is exposed to light. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as "solar panels". Almost all commercial PV cells consist of crystalline silicon, with a market share of 95%. Cadmium telluride thin-film solar cells account for the remainder. The common single-junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 to 0.6 volts.
A quantum dot solar cell (QDSC) is a solar cell design that uses quantum dots as the captivating photovoltaic material. It attempts to replace bulk materials such as silicon, copper indium gallium selenide (CIGS) or cadmium telluride (CdTe). Quantum dots have bandgaps that are adjustable across a wide range of energy levels by changing their size. In bulk materials, the bandgap is fixed by the choice of material(s). This property makes quantum dots attractive for multi-junction solar cells, where a variety of materials are used to improve efficiency by harvesting multiple portions of the solar spectrum.
Harry Albert Atwater, Jr. is an American physicist and materials scientist and is the Otis Booth Leadership Chair of the division of engineering and applied science at the California Institute of Technology. Currently he is the Howard Hughes Professor of Applied Physics and Materials Science and the director for the Liquid Sunlight Alliance (LiSA), a Department of Energy Hub program for solar fuels. Atwater's scientific effort focuses on nanophotonic light-matter interactions and solar energy conversion. His current research in energy centers on high efficiency photovoltaics, carbon capture and removal, and photoelectrochemical processes for generation of solar fuels. His research has resulted in world records for solar photovoltaic conversion and photoelectrochemical water splitting. His work also spans fundamental nanophotonic phenomena, in plasmonics and 2D materials, and also applications including active metasurfaces and optical propulsion.
In solar cell research, carrier multiplication is the phenomenon wherein the absorption of a single photon leads to the excitation of multiple electrons from the valence band to conduction band. In the theory of a conventional solar cell, each photon is only able to excite one electron across the band gap of the semiconductor, and any excess energy in that photon is dissipated as heat. In a material with carrier multiplication, high-energy photons excite on average more than one electron across the band gap, and so in principle the solar cell can produce more useful work.
A solar-pumped laser is a laser that shares the same optical properties as conventional lasers such as emitting a beam consisting of coherent electromagnetic radiation which can reach high power, but which uses solar radiation for pumping the lasing medium. This type of laser is unique from other types in that it does not require any artificial energy source.
Crosslight Software Inc. is an international company headquartered in greater Vancouver, British Columbia, Canada. Officially spun off from the National Research Council of Canada (NRC) in 1995, it provides Technology Computer Aided Design (TCAD) tools for semiconductor device and process simulations.
Nanocrystal solar cells are solar cells based on a substrate with a coating of nanocrystals. The nanocrystals are typically based on silicon, CdTe or CIGS and the substrates are generally silicon or various organic conductors. Quantum dot solar cells are a variant of this approach which take advantage of quantum mechanical effects to extract further performance. Dye-sensitized solar cells are another related approach, but in this case the nano-structuring is a part of the substrate.
Indium gallium arsenide phosphide is a quaternary compound semiconductor material, an alloy of gallium arsenide, gallium phosphide, indium arsenide, or indium phosphide. This compound has applications in photonic devices, due to the ability to tailor its band gap via changes in the alloy mole ratios, x and y.
Andreas Mandelis FRSC, FCAE, FAPS, FSPIE, FAAAS, FASME, is a Greek - Canadian physicist who is a professor and researcher in the department of Mechanical and Industrial Engineering at the University of Toronto. He is the director of the Center for Advanced Diffusion-Wave and Photoacoustic Technologies (CADIPT). and of the Institute for Advanced Non-Destructive and Non-Invasive Diagnostic Technologies (IANDIT) at the University of Toronto. He is an internationally recognized expert in thermophotonics. and is considered a pioneer in the fields of diffusion-wave, photothermal, and photoacoustic sciences and related technologies. His research interests encompass studies of physical energy conversion processes in condensed and biological matter as they impact instrumentation science and signal generation technologies with applications spanning the development of a wide spectrum of novel instrumentation, measurement and imaging techniques using optical-to-thermal, thermoelastic, electronic, ultrasonic and/or photonic energy conversion high-dynamic-range and high-sensitivity analytical methodologies, leading to advanced non-destructive / non-invasive diagnostic, inspection and monitoring technologies with major focus on advanced dynamic imaging instrumentation for industrial and biomedical applications. He is the inventor of a photothermal imaging radar which can detect tooth decay at an early stage, can detect the onset of cancerous lesions in soft tissues, cracks in teeth and monitor dental structural integrity over time. His research team also pioneered and patented 22 analytical instrumentation and measurement methodologies and metrologies.
Intermediate band photovoltaics in solar cell research provides methods for exceeding the Shockley–Queisser limit on the efficiency of a cell. It introduces an intermediate band (IB) energy level in between the valence and conduction bands. Theoretically, introducing an IB allows two photons with energy less than the bandgap to excite an electron from the valence band to the conduction band. This increases the induced photocurrent and thereby efficiency.
Olga Malinkiewicz is a Polish physicist, inventor of a method of producing solar cells based on perovskites using inkjet printing. She is a co-founder and the Chief Technology Officer at Saule Technologies.
Diana Huffaker FIEEE, FOSA is a physicist working in compound semiconductors optical devices. She is the current Electrical Engineering Department Chair at the University of Texas at Arlington. Previously, she served as the Sêr Cymru Chair in Advanced Engineering and Materials and as Science Director of the Institute of Compound Semiconductors at Cardiff University. Her work includes compound semiconductor epitaxy, lasers, solar cells, optoelectronic devices, plasmonics, and Quantum dot and nanostructured materials.
Alta Devices was a US-based specialty gallium arsenide (GaAs) PV manufacturer, which claimed to have achieved a solar cell conversion efficiency record of 29.1%, as certified by Germany's Fraunhofer ISE CalLab.
John E. Bowers is an American physicist, engineer, researcher and educator. He holds the Fred Kavli Chair in Nanotechnology, the director of the Institute for Energy Efficiency and a distinguished professor in the Departments of Electrical and Computer Engineering and Materials at University of California, Santa Barbara. He was the deputy director of American Institute of Manufacturing of Integrated Photonics from 2015 to 2022.
Anita Ho-Baillie is an Australian scientist who is the John Hooke Chair of Nanoscience at the University of Sydney. Her research considers the development of durable perovskite solar cells and their integration into different applications. She was named as one of the Web of Science's most highly cited researchers in 2019–2022.
Emily Warren is an American chemical engineer who is a staff scientist at the National Renewable Energy Laboratory. Her research considers high efficiency crystalline photovoltaics.
