Related papers: Angular constraint on light-trapping absorption en…
Light trapping in solar cells allows for increased current and voltage, as well as reduced materials cost. It is known that in geometrical optics, a maximum 4n^2 absorption enhancement factor can be achieved by randomly texturing the…
We use a rigorous electromagnetic approach to analyze the fundamental limit of light-trapping enhancement in grating structures. This limit can exceed the bulk limit of 4n^2, but has significant angular dependency. We explicitly show that…
We calculate the maximal absorption enhancement obtainable by guided mode excitation in a weakly absorbing dielectric slab over wide wavelength ranges. The slab mimics thin film silicon solar cells in the low absorption regime. We consider…
Understanding the maximal enhancement of solar absorption in semiconductor materials by light trapping promises the development of affordable solar cells. However, the conventional Lambertian limit is only valid for idealized material…
We propose a light-trapping structure offering a significant enhancement of photovoltaic absorption in transparent organic solar cells operating at infrared while the visible light transmission keeps sufficiently high. The main mechanism of…
We investigate the angular behavior of the upper bound of absorption provided by the guided modes in thin film solar cells. We show that the 4n^2 limit can be potentially exceeded in a wide angular and wavelength range using two-dimensional…
We report on the fabrication of two-dimensional periodic photonic nanostructures by nanoimprint lithography and dry etching, and their integration into a 1-{\mu}m-thin mono-crystalline silicon solar cell. Thanks to the periodic…
Enhancing the absorption and emission of electromagnetic waves over a broad range of wavelengths is a topic of fundamental and applied interest in photonics and energy research. In the context of light trapping in solar cells, for example,…
Epitaxially-grown quantum well and quantum dot solar cells suffer from weak light absorption, strongly limiting their performance. Light trapping based on optical resonances is particularly relevant for such devices to increase light…
We introduce a limit for the strength of coupling light into the modes of solar cells. This limit depends on both a cell's thickness and its modal properties. For a cell with refractive index n and thickness d, we obtain a maximal coupling…
It is currently possible to fabricate crystalline silicon solar cells with the absorber thickness ranging from a few hundreds of micrometers (conventional wafer-based cells) to devices as thin as $1\,\mu\mathrm{m}$. In this work, we use a…
We address the question of the optimal broadband absorption of waves in an open, dissipative system. We develop a general framework for absorption induced by multiple overlapping resonances, based on quasi-normal modes and radiative and…
Establishing the fundamental limit of nanophotonic light-trapping schemes is of paramount importance and is becoming increasingly urgent for current solar cell research. The standard theory of light trapping demonstrated that absorption…
We study light absorption by a dipolar absorber in a given environment, which can be a nanoantenna or any complex inhomogeneous medium. From first-principle calculations, we derive an upper bound for the absorption, which decouples the…
The ability to absorb light is indispensable for high efficient solar power generation. This places conflicting requirements on the structure of a solar cell: On one hand, it needs to have thick active layers to absorb more of the available…
A fundamental issue that limits the efficiency of many photoelectrochemical systems is that the photon absorption length is typically much longer than the electron diffusion length. Various photon management schemes have been developed to…
The incoherence of sunlight has long been suspected to have an impact on solar cell energy conversion efficiency, although the extent of this is unclear. Existing computational methods used to optimize solar cell efficiency under incoherent…
Silicon photodetectors operating at near-infrared wavelengths with high-speed and high sensitivity are becoming critical for emerging applications, such as Light Detection and Ranging Systems (LIDAR), quantum communications, and medical…
We theoretically demonstrate the fundamental limit in volume for given materials (e.g. Si, a-Si, CdTe) to fully absorb the solar radiation above bandgap, which we refer as solar superabsorption limit. We also point out the general…
We describe surface patterning strategies that permit high photon-collection efficiency together with high carrier-collection efficiency in an ultra-thin planar heterojunction organic photovoltaic cell. Optimized designs reach up to 50%…