Related papers: Fundamental limit of light trapping in grating str…
Saturation effects affecting absorption and fluorescence spectra of an atomic vapor confined in an Extremely Thin Cell (cell thickness $L < 1 \mu m$) are investigated experimentally and theoretically. The study is performed on the $D_{2}$…
In this paper, we simulate a front surface inverted pyramidal grating texture on 2 to 400 micron thick silicon and optimize it to derive maximum photocurrent density from the cell. We identify a one size fits all front grating period of…
The radiative open circuit voltage loss in a solar cell occurs because the absorptance spectrum near the band gap shows gradual increase rather than sharp step function like transition. This broadening effect has been attributed to band gap…
Since thin-film silicon solar cells have limited optical absorption, we explore the effect of a nanostructured back reflector to recycle the unabsorbed light. As a back reflector we investigate a 3D photonic band gap crystal made from…
We show a large enhancement of two-photon absorption processes in nanocrystal quantum dots and of light upconversion efficiency from the IR to the near-IR spectral regime, using a hybrid optical device in which near-IR emitting InAs quantum…
Gratings enable dispersive spectroscopy from the X-ray to the optical, and feature prominently in proposed flagships and SmallSats alike. The exacting performance requirements of these future missions necessitate assessing whether the…
Modern nanophotonic and meta-optical devices utilize a tremendous number of structural degrees of freedom to enhance light--matter interactions. A fundamental question is how large such enhancements can be. We develop an analytical…
III-V semiconductor quantum dots (QDs) are near-ideal and versatile single-photon sources. Because of the capacity for monolithic integration with photonic structures as well as optoelectronic and optomechanical systems, they are proving…
In the framework of $f(T)$ gravity, we focus on a weak-field and spherically symmetric solution for the Lagrangian $f(T)=T+\alpha T^{2}$, where $\alpha$ is a small constant which parameterizes the departure from General Relativity. In…
Topology has been revealed to play a fundamental role in physics in the past decades. Topological insulators have unconventional gapless edge states where disorder-induced back-scattering is suppressed. In photonics, such edge states lead…
By using an electrochemical gating technique with a new combination of polymer and electrolyte, we were able to inject surface charge densities n_2D as high as 3.5 \times 10^15 e/cm^2 in gold films and to observe large relative variations…
The thermodynamic limit of photovoltaic efficiency for a single-junction solar cell can be readily predicted using the bandgap of the active light absorbing material. Such an approach overlooks the energy loss due to non-radiative…
It is shown here that rendering the width of nano-grooves into a tunable parameter presents a new means of light trapping in subwavelength gratings. Particularly, in gratings with groove-widths below 150 nm, the plasmon coupling between the…
We develop the theoretical foundation for primary objective grating (POG) telescopy. In recent years, a wide range of telescope designs that collect the light over a large grating and focus it with a secondary receiving optic that is placed…
The design of metallic contact grids on the front side of thermophotovoltaic cells is critical since it can cause significant optical and electrical resistive losses, particularly in the near field. However, from the theoretical point of…
We optimized micro-holes in a thin slab for fast Si photodetectors at wavelength 800-950nm. Lateral modes are shown to be responsible for the effective light trapping. Small disorder and cone hole shapes helped achieve uniform quantum…
Recently, we have suggested dielectric metamaterial composed as an array of submicron dielectric spheres located on top of an amorphous thin-film solar cell. We have theoretically shown that this metamaterial can decrease the reflection and…
Trapping lithium with a big number in a simplified experimental setup has difficulties and challenges today. In this paper, we experimentally demonstrate the enhancement of \textsuperscript{6}Li trapping efficiency in a three-dimensional…
Nano-scaled metallic or dielectric structures may provide various ways to trap light into thin-film solar cells for improving the conversion efficiency. In most schemes, the textured active layers are involved into light trapping structures…
Diamond 1 - 10 micrometers thick membranes are platform for photonic, quantum and opto-mechanic devices with applications across UV-IR spectral ranges. IR characterization of diamond gratings in reflection and transmission showed a change…