The possibility of using a nanoporous Ge layer formed by implantation with 115 In + ions on monocrystal c-Ge substrate as an antireflection optical coating (In:PGe) was studied. For this purpose, ion wafers performed at energy E=30 keV, current density in the beam J=5 μA/cm 2 , and dose D=1.8· 10 16 ion/cm . It shown that fabricated In:PGe spongy layer, which consists intertwining nanowires, is...

In this paper, comparative study of p type and n type solar cells are described using two popular solar cell analyzing software AFORS HET and PC1D. We use SiNx layer as Antireflection Coating and a passivated layer Al2O3 .The variation of reflection, absorption, I-V characteristics, and internal and external quantum efficiency have been done by changing the thickness of passivated layer and ARC...

We demonstrate a frequency tunable external cavity terahertz quantum cascade laser using an abutted antireflection-coated silicon lens to reduce facet reflection and as a beam-forming element, with an external grating providing frequency selective optical feedback. Angle tuning of the grating allows a single longitudinal mode of the laser ridge to be selected, resulting in discontinuous tuning ...

We investigate experimentally the influence of the grating reflectivity, grating resolution, and diode facet antireflection (AR) coating on the intrinsic linewidth of an external-cavity diode laser built with a diffraction grating in a Littrow configuration. Grating lasers at 399, 780, and 852 nm are determined to have typical linewidths between 250 and 600 kHz from measurements of their freque...

We present the measurements and the theoretical model on the frequency dependent noise temperature of a lattice cooled hot electron bolometer (HEB) mixer in the terahertz frequency range. The experimentally observed increase of the noise temperature with frequency is a cumulative effect of the non-uniform distribution of the high frequency current in the bolometer and the charge imbalance, whic...

In previous reports on the sensitivity to layer thickness errors of DWDM and similar narrow band filter coatings, it was noted that the effect of monitoring errors that occur before the turning point appear more severe than those that occur after it. No satisfactory explanation had been found for this result. We report on the search for the explanation of that and related findings. The previous...

We have doubled the frequency of a single mode distributed Bragg reflection (DBR) semiconductor laser. The laser is optically locked to an external enhancement ring resonator that contains an antireflection coated potassium niobate crystal. Unlike Fabry-Perot cavity lasers the DBR laser is found to operate in only one longitudinal mode and allows stable second harmonic generation. We present th...

Prisms and slabs made of high-refractive-index materials such as ZnSe, Ge, and Si can be designed as broadband, 50%-50%, beam splitters (BSs) for obliquely incident s- polarized light in the near- and mid-IR. The beam-splitting face of the prism or slab is uncoated, while the exit face is antireflection coated. The split beams travel in orthogonal directions when light is incident at the Brewst...

Calculations of the longitudinal mode functions for the electric field of a compound-cavity laser show that the loss and gain coefficients are given by the Airy formula, as a function of the mode frequencies. Further, when the external cavity is longer than the gain-medium cavity, the frequency dependence of the gain is stronger than that of the loss, even when the intracavity surfaces are anti...