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In this paper, we analyze 1-D and 2-D arrays of photonic crystal waveguide section lasers in a square lattice of air holes. These arrays can provide much higher emitted power than a single microcavity laser, without significantly increasing the threshold power. We also propose a few ways to reduce the emission of light from the side lobes, and to collect light emissions from distinct elements in a 2-D array and couple them into a single-mode waveguide. [ABSTRACT FROM PUBLISHER]

This paper discusses the growth of In(Ga)As quantum dots (QDs) and nanowires by metal-organic chemical vapor deposition and their application to optoelectronic devices. The performance characteristics of QD lasers and QD photodetectors as well as the selective area growth of QDs for integrated devices are reported [ABSTRACT FROM PUBLISHER]

Picosecond bleaching dynamics of vertically stacked self-assembled quantum dots (QDs) is investigated by means of time-resolved pump-probe differential reflection spectroscopy (TRDR) at room temperature (RT). We observe that the absorption spectrum, which represents the QD density of states at RT, is strongly shifted with respect to the photoluminescence spectrum. This shift can not be interpreted by carrier emission and re-trapping alone. TRDR allows us to study the dynamics of the pump generated carriers within the QDs. From the time-resolved measurements, we detect that the bleaching decay time has a strong energy dependence and is dominated by radiative and nonradiative recombination at low energy and by carrier emission at high energy. [ABSTRACT FROM PUBLISHER]

An InGaAs quantum-dot (QD) laser integrated with a low-loss waveguide is demonstrated. Selective-area epitaxy is used to simultaneously form the QDs that form the active region of the laser and quantum wells (QWs) that form the waveguide section of the integrated devices. The losses in the active and passive sections of the integrated devices are 6 and 3 cm -1, respectively. Very low losses in the waveguide section are due to a large difference of 200meV in the bandgap energies of the selectively grown QDs and QWs [ABSTRACT FROM PUBLISHER]

We have used ion implantation for erbium doping of mesoporous silicon microcavities. Optically active erbium-doped microcavities with Q factors in excess of 1500 have been demonstrated. We observed strong modification of the emission properties of the erbium in the microcavity with an accompanying cavity enhancement factor of 25. In addition, power- and temperature-dependent photoluminescence measurements indicate that erbium-implanted porous silicon has excitation mechanism very similar to that of erbium in a crystalline silicon host. [ABSTRACT FROM AUTHOR]

The electrical isolation of p-type GaAs[sub 1-x]N[sub x] epilayers (x=0.6%, 1.4%, and 2.3%) produced by H, Li, C, or O ion implantation and its thermal stability in nominally undoped GaAs[sub 0.986]N[sub 0.014] epilayers were investigated. Results show that the sheet resistance of p-type GaAsN layers can be increased by about five or six orders of magnitude by ion implantation and the threshold fluence (F[sub th]) to convert a conductive layer to a highly resistive one depends on the original free carrier concentration and the number of implantation-generated atomic displacements, and does not depend on the nitrogen content. The thermal stability of electrical isolation in GaAsN depends on the ratio of the final fluence to the threshold fluence. The electrical isolation can be preserved up to 550 °C when the accumulated fluence is above 3.3 F[sub th]. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Reports that arsenic ion implantation with thermal annealing was used to shorten the response times of GaAs-based saturable absorber structures. Ultrafast absorption bleaching measurements; Decrease in recovery time with increasing the implantation dose.

Measures the nonlinear optical absorption of arsenic and oxygen implanted epitaxial gallium arsenide (GaAs) for a range of ion doses and annealing temperatures. Response time; Metal organic vapor deposition; Performance of the structures as modulators; Nonbleachable losses.

Investigates the use of proton irradiation to induce wavelength shifting in gallium arsenide quantum well lasers. Maximum length of the wavelength shift; Magnitude of waveguide irradiation; Importance of the technique for wavelength-division-multiplexing.

Presents an electrical and structural analysis of high-dose silicon (Si) implantation in gallium nitride (GaN). Properties of Si-implanted GaN in different doses; Comparison between silicon and argon implantation; Details on the impact of the implant activation annealing sequence on the defect concentration.

Demonstrates the use of proton irradiation and subsequent rapid-thermal annealing to create intermixing in GaAs-AlGaAs quantum wells. Observation of very large energy shifts with no apparent saturation; Explanation of the effect in terms of the dilute irradiation damage; Implication of high point defect fraction in light ions for intermixing.

Examines the ultrafast carrier trapping in high energy ion implanted gallium arsenide (GaAs). Correlation between carrier trapping time and implantation dose; Independence of sheet resistance on implantation dose; Observation of conductivity activation energies for arsenic, gallium and oxygen ion implanted and annealed GaAs.

Investigates high resistivity and picosecond carrier lifetime of gallium arsenide (GaAs) implanted with megaelectronVolt gallium ions at high fluences. Strain field exhibited by the implanted samples; Effects of annealing the samples at the temperature of 600 degrees Celsius; Optoelectronic device applications of gallium-implanted GaAs.