Related papers: Possible atomic structures for the sub-bandgap abs…
Hyperdoped metastable sulfur atoms endow crystalline silicon with a strong sub-bandgap light absorption. In order to explore such metastable states, we develop a new high-throughput first-principles calculation method to search for all of…
Amorphous hydrogenated silicon (a-Si:H) is an important material for surface defect passivation of photovoltaic silicon (Si) wafers in order to reduce their recombination losses. The material is however unstable with regards to hydrogen (H)…
We present a first-principles study of geometrical structure and energetics of hydrogen adsorbed on hexagonal single-walled silicon nanotubes (SiNTs). The adsorption behaviors of hydrogen molecules in SiNTs are investigated. The binding…
We develop an analytical model to describe sub-bandgap optical absorption in two-dimensional semiconducting transition metal dichalcogenide (s-TMD) nanoflakes. The material system represents an array of few-layer molybdenum disulfide…
Harnessing low energy photons is of paramount importance for multi-junction high efficiency solar cells as well as for thermo-photovoltaic applications. However, semiconductor absorbers with bandgap lower than 0.8 eV have been limited to…
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…
The design and fabrication of a metal-dielectric-metal absorber that achieves strong absorption from the ultraviolet (UV) to the near-infrared (near-IR) spectrum are presented. The proposed nanostructure consists of a periodic titanium (Ti)…
Silicon's inherently indirect bandgap severely limits its radiative efficiency, posing a fundamental challenge to the development of practical silicon-based light sources. While strategies such as nanoscale confinement of electrons and…
The discovery of superconductivity at 203K in SH$_3$ is an important step toward higher values of $T_c$. Predictions based on state-of-the-art DFT for the electronic structure, including one preceding experimental confirmation, showed the…
Strong light-matter interactions in silicon metasurfaces give rise to photothermal nonlinearities. While the effect of this strong coupling on light has been extensively studied, its impact on matter remains largely unexplored. Here, we…
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 have investigated the intersubband transitions of surface state electrons (SSE) on liquid $^3$He induced by microwave radiation at temperatures from 1.1 K down to 0.01 K. Above 0.4 K, the transition linewidth is proportional to the…
Influence of composition and external hydrostatic pressure on the structural, electronic, and optical properties of the CuGa1-xAlxS2 (x=0, 0.25, 0.5, 0.75, 1.0) chalcopyrite semiconductor was analyzed by means of the first-principles…
Encapsulation layers are explored for passivating the surfaces of silicon to reduce optical absorption in the 1500-nm wavelength band. Surface-sensitive test structures consisting of microdisk resonators are fabricated for this purpose.…
Compound semiconductors have been the predominant building blocks for the current mid-infrared thermophotovoltaic devices relevant to sub-2000 K heat conversion and power beaming. However, the prohibitively high cost associated with these…
Hyperdoping consists of the intentional introduction of deep-level dopants into a semiconductor in excess of equilibrium concentrations. This causes a broadening of dopant energy levels into an intermediate band between the valence and…
We report on a study of the electromagnetic response of three different families of high-T_c superconductors that in combination allowed us to cover the whole doping range from under- to overdoped. The discussion is focused on the ab-plane…
The absorption length, $\lambda_{abs}$, of light with wavelengths between 0.95 and 1.30$~\mu$m in silicon irradiated with 24$~$GeV/c protons to 1$~$MeV neutron equivalent fluences between 0 and $8.6 \times 10^{15}~$cm$^{-2}$ has been…
Recently, a homogenization procedure has been proposed, based on the tight lower bounds of the Bergman-Milton formulation, and successfully applied to dilute ternary nanocomposites to predict optical data without using any fitting…
A theoretical framework incorporating atomic-level interfacial details is derived to include the electronic structure of buried interfaces and describe the behavior of charge carriers in heterostructures in the presence of finite…