Solar absorptances are often derived from the reflectance values measured with devices which make use of integrating spheres. Instruments of this type can be operated in two different ways, according to whether spectral or integrated reflectances are measured. Though solar absorptances derived from spectral data are inherently more accurate, some commercially available reflectometers are found ...

An integrating-sphere system has been designed and constructed for multiple optical properties measurement in the IR spectral range. In particular, for specular samples, the absolute transmittance and reflectance can be measured directly with high accuracy and the absorptance can be obtained from these by simple calculation. These properties are measured with a Fourier transform spectrophotomet...

The fundamental sheet conductance of graphene can be directly related to the product of its absorption coefficient, thickness and refractive index. The same can be done for graphene's fundamental opacity if the so-called thin-film limit is considered. Here, we test mathematically and experimentally the validity of this limit on graphene, as well as on thin metal and semiconductor layers. Notabl...

The paper presents results concerning CVD thin films of transition metals (W and Mo) and their composite structures W02:W and MoOZ:Mo, as well as WO films. The composite structure materials 3 consisting of a suspension of metallic molybdenum or tungsten grains in a host matrix of metal dioxide demonstrate significant solar absorptance coupled with a high infrared reflectance, which is necessary...

We report on the enhancement of system detection efficiency in a superconducting nanowire single-photon detector (SNSPD) by applying the optical cavity structure. The nanowire was made using 4nm-thick NbN thin films and covered with an SiO cavity and Au mirror designed for 1300–1600 nm wavelengths. The device is mounted into fibercoupled packages, and installed in a practical multichannel syste...

The thin-film limit is derived by a nonconventional approach and equations for transmittance, reflectance and absorptance are presented in highly versatile and accurate form. In the thin-film limit the optical properties do not depend on the absorption coefficient, thickness and refractive index individually, but only on their product. We show that this formalism is applicable to the problem of...

We describe progress in the development of a calibration target for use in the EOS-MLS 2.5 THz radiometer on NASA's CHEM-1 spacecraft. Although the intended use is as a stable, isothermal black body load at a frequency of 2.5 THz, the design is suitable for use throughout ,the far-infrared (FIR). A wedge design is used for the target body to. enhance the emissivity to desired levels at 2.5 THz....

We present superconducting nanowire single-photon detectors (SSPDs) on non-periodic dielectric multilayers, which enable us to design a variety of wavelength dependences of optical absorptance by optimizing the dielectric multilayer. By adopting a robust simulation to optimize the dielectric multilayer, we designed three types of SSPDs with target wavelengths of 500 nm, 800 nm, and telecom rang...

UNLABELLED Large-area periodically aligned silicon nanopillar (PASiNP) arrays were fabricated by magnetic sputtering with glancing angle deposition (GLAD) on substrates coated by a monolayer of close-packed polystyrene (PS) nanospheres. The structure of PASiNP arrays could be manipulated by changing the diameter of PS nanospheres. Enhanced light absorptance within a wavelength range from 300 to...