We demonstrate near-unity, broadband absorbing optoelectronic devices using sub-15 nm thick transition metal dichalcogenides (TMDCs) of molybdenum and tungsten as van der Waals semiconductor active layers. Specifically, we report that near-unity light absorption is possible in extremely thin (<15 nm) van der Waals semiconductor structures by coupling to strongly damped optical modes of semicond...

In order to effectively realize and control the critical coupling, a graphene-based hyperbolic metamaterial has been proposed to replace the absorbing thin film in the critically coupled resonance structure. Our calculations demonstrate that the critical coupling effect (near-perfect light absorption) can be achieved at the near-infrared wavelength by using this layered structure, while the cri...

AM-6 with high intensity visible light absorption at 400-800 nm was synthesized via a hydrothermal route in the presence of F(-) ions. Structure characterization and DFT calculations indicate that the unusual optical properties originate from the connection of octahedral VO(6) wires with distorted tetrahedral VO(4) units, which are stabilized in the framework of AM-6.

Laboratory measurements were performed to characterize the geometrical effects in the calibration of the NASA's cloud absorption radiometer (CAR). The measurements involved three integrating sphere sources (ISSs) operated at different light levels and experimental setups to determine radiance variability. The radiance gradients across the three ISS apertures were 0.2%-2.6% for different visible...

We report the absorption cross-section of colloidal InAs quantum dots of mean radii from 1.6 to 3.45 nm. We find excellent agreement between the measured results and calculated values based on a model of small-particle light absorption. The absorption cross-section per dot is 6.2 x 10(-16)R(3) cm(2) at 2.76 eV and 3.15 x 10(-16)R(1.28) cm(2) at the first-exciton absorption peak, with the dot ra...

Photoelectrochemical cells that efficiently split water into oxygen and hydrogen, "the fuel of the future", need to combine robust water oxidation catalysts at the anode (2H(2)O --> O(2) + 4H(+) + 4e(-)) with hydrogen reduction catalysts at the cathode (2H(+) + 2e(-)--> H(2)). Both sets of catalysts will, ideally, operate at low overpotentials and employ light-driven or light-assisted processes...

It is shown that absorption of the excitation light can lead to substantial systematic errors in fluorescence measurements of equilibrium constants for formation of protein-ligand complexes. The assumptions about the optical arrangement of the fluorescence spectrometer involved in the calculation of the correction of this absorption are discussed. A general semiempirical correction procedure wh...