Volume 86, Issue 3, 01 August 1999
Index of content:
- LASERS, OPTICS, AND OPTOELECTRONICS (PACS 42)
86(1999); http://dx.doi.org/10.1063/1.370866View Description Hide Description
The transmission properties of different metallic photonic lattices (square and rectangular) have been experimentally studied. A numerical algorithm based on time domain finite differences has been used for simulating these photonic structures. The introduction of defects in the two-dimensional metallic lattice modifies its transmission spectrum. If metal rods are eliminated from (or added to) the lattice, extremely narrow peaks are observed at some particular frequencies below (or above) the band pass edge.
86(1999); http://dx.doi.org/10.1063/1.370867View Description Hide Description
Hexa-deutero dimethylsulfoxide solutions of terphenyl-based and complexes functionalized with a triphenylene antenna chromophore exhibit room temperature near-infraredluminescence at wavelengths of interest for the optical telecommunicationnetwork (∼1330 and ∼1550 nm). The sensitizing process takes place through the triplet state of triphenylene as can be concluded from the oxygen dependence of the sensitized luminescence. A significant fraction of the excited triphenylene triplet state is quenched by oxygen, instead of contributing to the population of the luminescent state of the lanthanide ion. The luminescence lifetimes of the triphenylene-functionalized lanthanide complexes ((2)Ln) are in the range of microseconds with a lifetime of 18.6 μs for (2)Yb, 3.4 μs for (2)Er, and 2.5 μs for (2)Nd in These luminescence lifetimes seem almost completely dominated by the vibrational quenching by the organic groups in the polydentate ligand and solvent molecules, which leads to low overall luminescence quantum yields.
86(1999); http://dx.doi.org/10.1063/1.370868View Description Hide Description
Multiple phase gratings are written in pure, Yb- and P-doped crystals: a fast grating and a slow grating with substantially different response times compensate each other. Doping and thermal treatments have strong influences on the behavior of both gratings. Reduction treatments of Yb-doped samples lead to a significant decrease of the response time of the slow grating, while that of the fast grating is diminished by more than two orders of magnitude. P doping significantly increases the response time of the fast grating. Possible origins of both gratings are discussed.
86(1999); http://dx.doi.org/10.1063/1.370869View Description Hide Description
Based on the bidirectional fast Fourier transform beam propagation method (FFT-BPM), a self-consistent Fabry-Pérot waveguide laser model has been developed. By using the bidirectional FFT-BPM and the attenuationeffect of pumping and resultant lasers within the waveguide cavity, the interference effect and physical behaviors of the population inversion longitudinal and transversal spatial effects were observed. The resultant laser power is saturated if the waveguide is longer than a critical length, which is a function of the pumping power. Moreover, the resultant laser power density is a nonuniform function along the longitudinal dimension within the waveguide cavity.
86(1999); http://dx.doi.org/10.1063/1.370870View Description Hide Description
Packaging-induced strain is studied in high-power semiconductor lasers by a noninvasive optical technique. Fourier-transform photocurrentmeasurements with intentionally strained laser array devices for 808 nm emission reveal spectral shifts of optical transitions within the active region. These shifts by up to 10 meV serve as a measure for the strain status within the active layer of the devices and are compared with model calculations. For different packaging architectures we quantify the strain portion which is transmitted to the optically active region of the semiconductor device.