A photonic crystal waveguide with silicon on insulator in the near-infrared band

A two-dimensional (2D) photonic crystal waveguide in the Gamma-K direction with triangular lattice on a silicon-on insulator (SOI) substrate in the near-infrared band is fabricated by the combination of electron beam lithography and inductively coupled plasma etching. Its transmission characteristics are analysed from the stimulated band diagram by the effective index and the 2D plane wave expansion (PWE) methods. In the experiment, the transmission band edge in a longer wavelength of the photonic crystal waveguide is about 1590 nm, which is in good qualitative agreement with the simulated value. However, there is a disagreement between the experimental and the simulated results when the wavelength ranges from 1607 to 1630 nm, which can be considered as due to the unpolarized source used in the transmission measurement.

Enhanced near-infrared photoluminescence from isoelectronic luminescent centers in sulfur-implanted silicon with copper or silver coimplantation

Enhanced near-infrared photoluminescence (PL) from sulfur-related isoelectronic luminescent centers in silicon was observed from thermally quenched sulfur-implanted silicon in which additional copper or silver ions had been coimplanted. The PL from the sulfur and copper coimplanted silicon peaked between 70 and 100 K and persisted to 260 K. This result strongly supports the original conjecture from the optical detection of magnetic resonance studies that the strong PL from sulfur-doped silicon comes from S-Cu isoelectronic complexes [Frens , Phys. Rev. B 46, 12316 (1992); Mason , ibid. 58, 7007 (1998).]. (c) 2007 American Institute of Physics.

Study of microstructure of high stability hydrogenated amorphous silicon films by Raman scattering and infrared absorption spectroscopy

The microstructure, hydrogen bonding configurations and hydrogen content of high quality and stable hydrogenated amorphous silicon (a-Si:H) films prepared by a simple ''uninterrupted growth/annealing" plasma enhanced chemical vapor deposition technique have been investigated by Raman scattering and infrared absorption spectroscopy. The high stability a-Si:H films contain small amounts of a microcrystalline phase and not less hydrogen (10-16 at. %), particularly, the clustered phase hydrogen, Besides, the hydrogen distribution is very inhomogeneous. Some of these results are substantially distinct from those of conventional device-quality n-Si:H film or stable cr-Si:H films prepared by the other techniques examined to date. The stability of n-Si:H films appears to have no direct correlation with the hydrogen content or the clustered phase hydrogen concentration. The ideal n-Si:H network with high stability and low defect density is perhaps not homogeneous. (C) 1998 American Institute of Physics.

Intense room temperature near infrared emission from Al (3+) and Yb3+ ions

Intense near infrared emission was observed from Al3+ and Yb3+ ions co-implanted SiO2 film on silicon. It was found that the addition of Al3+ ions could remarkably improve the photoluminescence efficiency of Yb3+-implanted SiO2 film. No excitation power saturation was observed and trivial temperature quenching factor of 2 was achieved.

Design of spectrometer based on volume phase grating for near infrared range

In order to design and fabricate a spectrometer for the infrared range widely used in the different applications, Volume Phase Grating (VPG) with. low Polarization Dependence Loss (PDL) and high efficiency has been adopted as the dispersion element. VPG is constructed by coating an optical substrate with a thin film of dichromated. gelatin and exposing the film to two mutually coherent laser beams to form index modulation. The diffraction efficiency for a VPG is governed by Bragg effects. The depth (d) and index modulation contrast of the grating structure control the efficiency at which the light is diffracted when the Bragg condition is satisfied. Gradient index lens with high performance and low aberration are used as collimating system instead of standard lens. The spot diagrams and MTF curve of the collimating lens are shown in the paper. The receive system is InCaAs photodiode (PD) array including 512 pixels with 25 mum pitch. The spectrum resolution of the spectrometer reaches to 0.2nm and wavelength accuracy is 40pm.

Near infrared lights emission of Ar-40(16+) impacting on metal surfaces

The highly charged ion Ar-40(16+) with the velocity (kinetic energy E (K)=150 keV, velocity V=8.5x10(5) m/s) smaller than Bohr velocity (V (Bohr)=2.9x10(6) m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model.