摘要:

The profiles (spatial distributions) of injected carriers and current within a double‐heterostructure stripe‐geometry laser are described theoretically in a one‐dimensional‐flow model. The one‐dimensional model is solved exactly and found to yield comparatively simple analytical expresions even when both radiative (nonlinear) and nonradiative recombination are operative. In the case of a shallow proton bombardment or an oxide stripe, two coupled current components leak from under the stripe—an Ohmic current in thePlayer and a diffusion current in the active region. As an example, these wasted leakage currents are evaluated in detail and seen to depend strongly upon the laser design. Features of this work not present in previous analytical studies include incorporation of radiative recombination (Bn2) and a carrier‐concentration‐dependent diffusion coefficient, as well as development of a self‐consistent solution for the two current components.

ISSN:0021-8979    

DOI:10.1063/1.328008

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Data are presented showing that the threshold current density,Jth(T)∝exp(T/T0), of multiple quantum‐well InGaPAs‐InP heterostructure laser diodes, grown by LPE, exhibits a two‐regime behavior similar to that of conventional InGaPAs‐InP double‐heterojunction lasers. At temperatures below a break‐point temperature characteristic of the quaternary alloy,Jth(T) of these multiple quantum‐well laser diodes is less temperature dependent (i.e., largerT0, as high as 150 °C) than that of regular quaternary DH lasers. At temperatures above the break‐point temperature,Jth(T) is dominated by a poorly understood competing temperature‐dependent nonradiative recombination process. In this range theT0of these multiple quantum‐well diodes is similar to that of ordinary InGaPAs‐InP DH diodes but, because of the large number of layers and large lower‐temperatureT0, is not apt to be caused by defects at heterointerfaces.

ISSN:0021-8979    

DOI:10.1063/1.328009

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The extremely complex kinetics of pumping, quenching, and absorption in krypton fluoride excimer lasers is now relatively well understood. A single comprehensive kinetic model, solved approximately by analytic means and more exactly by a computer code of moderate size, is capable of simulating with great accuracy the performance of KrF lasers pumped by e‐beam sustained discharge, and self‐sustained discharge. We present the results of applications of this model to interpret and predict the limiting behavior and scaling of KrF lasers. A measure of remaining uncertainties is discussed.

ISSN:0021-8979    

DOI:10.1063/1.328010

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Nuclear pumped lasers are characterized by high‐threshold neutron fluxes and low gain. This is due primarily to the fact that the fissile gas, which has the largest partial pressure and hence has the largest fraction of fission energy deposited in it, is not the lasing species. The closer the fissile gas can be coupled to the actual lasing process, the more efficient the laser will be. In this paper, a model for a potential new nuclear‐pumped HF laser is presented. Using a235UF6‐H2gas mixture, a peak gain of about 50%/m and a threshold neutron flux of <1014/cm2 s are predicted. Recommendations are made concerning optimum use of the new system.

ISSN:0021-8979    

DOI:10.1063/1.328011

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The semiconductor Raman laser has been realized by using a GaP crystal. Pumping is made by aQ‐switched YAG laser operating at 1.064 &mgr;m. The round‐trip loss in the Fabry‐Perot resonator is 2% or less. The Raman scattering from LO phonons stimulates in the ⟨100⟩ direction, while the forward and backward Raman scattering from TO phonons stimulate in the ⟨110⟩ direction. This semiconductor Raman laser is promising as a semiconductor far‐infrared radiation source.

ISSN:0021-8979    

DOI:10.1063/1.328012

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The electron‐beam‐pumped XeF laser operating on theB‐XandC‐Atransitions shows a strong temperature dependence. Fluorescence, gain, and laser output measurements in Ar/Xe/NF3and Ne/Xe/NF3mixtures are reported for temperatures from 300 to 600 K. Elevated temperatures cause stronger mixing between theBandCstates as well as among the vibrational levels within theBstate. Together with the higher ground‐state dissociation rate this leads to an improvement of theB‐Xlasing for 300k <T< 500 K, whereas theC‐Alaser emission ceases under these conditions.

ISSN:0021-8979    

DOI:10.1063/1.328013

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Theoretical and numerical analysis of the multipass amplifier illustrates its flexibility in applications ranging from efficient high‐power pulse amplification to short‐pulse generation with great amplitude and pulse‐width stability.

ISSN:0021-8979    

DOI:10.1063/1.328014

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The single‐mode and multimode free‐running dye lasers are examined as possible sources for generating power‐squared corrected two‐photon absorption spectra. The observed differences between the two sources is attributed to the presence of mode noise in the multimode output, which yields inaccuracies in spectra when used as a source for two‐photon spectroscopy. Using an accurate reference spectrum generated with the single‐mode source, the utility of ratioing to obtain accurate spectra with the multimode laser is demonstrated. Alternate techniques for obtaining power‐squared corrected two‐photon spectra with the multimode laser are considered.

ISSN:0021-8979    

DOI:10.1063/1.328015

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

In the interaction of a coupled, three‐optical‐waveguide system, it is shown that, even when there is no direct coupling between two phase‐matched waveguides, the high‐efficiency coupling between them can be established by the indirect coupling through the third phase‐mismatched waveguide. It is also shown that the coupling between the two phase‐matched waveguides, having direct coupling, can be effectively vanished by introducing the third phase‐mismatched waveguide.

ISSN:0021-8979    

DOI:10.1063/1.328016

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Tunable single sidebands in the infrared were generated by electro‐optically mixing a 14–18‐GHz tunable microwave and a fixed‐frequency CO2laser signal, both circularly polarized, in a resonant modulator. With 10 W microwave drive power, a peak single‐sideband conversion efficiency of 280 &mgr;W/W laser power was achieved. Sideband discrimination was 30 dB throughout the tuning range.

ISSN:0021-8979    

DOI:10.1063/1.328017

出版商:AIP    

年代:1980

数据来源: AIP