摘要:

The threshold current and the wavelength of a high‐power ridge waveguide AlGaAs graded index seperate confinement heterostructure quantum well laser have been studied in strong magnetic fields up to 20 T, to simulate the complete quantum confinement of carriers in a quantum box laser. It will be shown both experimentally and theoretically that the threshold current is increased by the application of a strong magnetic field, while its temperature sensitivity is reduced. It will further be shown that at low temperatures (T<100 K) laser emission occurs via both free carrier and excitonic transitions, while at higher temperatures (T>100 K) exciton laser emission is only observed after application of a strong magnetic field, i.e., reduction of the dimensionality.

ISSN:0003-6951    

DOI:10.1063/1.101373

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

Transmission measurements show a large decrease of the absorption saturation in semiconductor‐doped glasses which have been exposed to intense absorbing light. A simple saturation model including nonradiative and Auger recombination and an unsaturable part of the absorption, interpreted as free‐carrier absorption, explains the observed changes.

ISSN:0003-6951    

DOI:10.1063/1.101249

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

We report experimental results on gain medium area scaling of laser output power for large‐area, transverse rf discharge excited carbon dioxide lasers. Power extraction to 20 kW/m2has been achieved, indicating the significant potential of this technique.

ISSN:0003-6951    

DOI:10.1063/1.101250

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

A fully adjustable self‐limiter and optical clamp in a geometry suitable for use in a fiber optics context is demonstrated. Edge‐coupled light into a silicon thin film on a doped silicon substrate lowers the refractive index of the guiding film and eventually brings it to the cutoff condition. Furthermore, by varying the amount of light incident on the nonlinear substrate and the nonlinear film waveguide, a fully adjustable limiting action is obtained. It is shown that absorption effects are not important at power levels compatible with fiber optics, making the limiter highly damage resistant.

ISSN:0003-6951    

DOI:10.1063/1.101251

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

We have applied the technique of laser‐induced etching to fabricate rib waveguides on a GaAs/AlGaAs heterostructure system. Light confinement of these guides was controlled by varying the depth of the etched trenches. Additionally, we have demonstrated directional couplers and two‐level waveguides using theinsitudepth control of this single‐step process.

ISSN:0003-6951    

DOI:10.1063/1.101252

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

The fidelity of phase conjugation by degenerate four‐wave mixing in ruby and semiconductor‐doped glasses has been measured by means of our own modified Twyman–Green interferometer [Opt. Lett.14, 183 (1989)] implementing two phase conjugate mirrors. It is shown that the fidelity of phase conjugators with an OG530 color filter as the nonlinear medium reaches a value of 99%. The fidelity of ruby is also reported. Additionally the effect of the recording system on the value of the fidelity is discussed.

ISSN:0003-6951    

DOI:10.1063/1.101253

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

We calculate an expression for the fine structure in the field fluctuation spectrum of a semiconductor laser in terms of accessible device parameters. We measure the spectrum of an InGaAsP DFB laser and determine the linewidth, relaxation resonance, and damping versus current. From the relation between damping and current, we determine the nonlinear gain coefficient.

ISSN:0003-6951    

DOI:10.1063/1.101254

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

Conditions for stabilization of in‐phase or out‐of‐phase array eigenmodes in diffraction coupled diode laser arrays are derived and applied to several array architectures. The analysis predicts that the discrimination between these two eigenmodes is strongest in arrays with half Talbot distance long free‐propagation region. In this geometry, the out‐of‐phase and in‐phase near fields are, respectively, reproduced and channeled halfway between the original channel locations.

ISSN:0003-6951    

DOI:10.1063/1.101255

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

This letter reports the design and performance of a scaled, injection‐controlled XeF(C→A) laser pumped by a repetitively pulsed, high current density electron beam with a temporal duration of 10 ns full width at half maximum. Injection of a 2 mJ pulse at 486.8 nm having a spectral width of <0.005 nm resulted in an amplified output of 0.7 J corresponding to energy density and efficiency values of 1.5 J/land 1.2%.

ISSN:0003-6951    

DOI:10.1063/1.101256

出版商:AIP    

年代:1989

数据来源: AIP

摘要:

We study the operation of an all‐optical, integrated, beam scanning device based on nonlinear grating coupling between radiative and guided‐wave beams. Diffusive nonlinearities are considered and the salient features are compared with previous experimental results obtained in ZnS waveguides.

ISSN:0003-6951    

DOI:10.1063/1.101257

出版商:AIP    

年代:1989

数据来源: AIP