摘要:

Sideband power has been generated at frequencies offset approximately 10 GHz from a CO2laser line,P(20)00°1→10°0, in a thin slab of GaAs. Efficent nonlinear interaction was accomplished by having the thin slab serve as both an optical waveguide and a microwave minigap ridge waveguide. With a 20‐W microwave signal applied to a 30‐&mgr;m‐thick optical waveguide contained in a 0.9‐cm‐long ridge section, about 0.4% laser power has been transferred into the sidebands, consistent with the theory.

ISSN:0003-6951    

DOI:10.1063/1.1655469

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

The spectral radiance from a cylindrically shaped laser‐produced plasma in the ultraviolet region (200–300 nm) is shown to be 2–3 times greater than that produced by a xenon flashlamp of comparable size and input energy. The experimental results suggest several advantages of laser‐produced plasmas as sources for the optical pumping of lasers.

ISSN:0003-6951    

DOI:10.1063/1.1655470

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Swirl defects in as‐grown silicon single crystals could be observed directly in a transmission electron microscope after application of a special sample preparation method. Complicated dislocation loops were found at positions of individual swirl defects which had been revealed as hillocks rather than as etch pits by a modified Sirtl etch.

ISSN:0003-6951    

DOI:10.1063/1.1655471

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

The mobility distribution in a semiconducting epitaxial film on insulating substrate is derived from transmission line analysis ofQ‐Vdata combined with theC‐Vmethod for obtaining impurity distribution. The mobility thus obtained is found to agree with that obtained by Hall effect measurements for ann‐type epitaxial GaAs layer on semi‐insulating Cr‐doped GaAs substrate.

ISSN:0003-6951    

DOI:10.1063/1.1655472

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

We report here the results of an HF‐laser experiment in which an intense electron beam is used to initiate high‐pressure room‐temperature H2/F2mixtures. The maximum laser energy was 2.3 kJ in a 35‐nsec (FWHM) pulse with a mixture of 360‐Torr F2, 140‐Torr O2, 100‐Torr SF6, and 100‐Torr H2. Electrical efficiency for the laser was as high as 200%. The maximum chemical efficiency was 5.2%.

ISSN:0003-6951    

DOI:10.1063/1.1655473

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Laser gain measurements at 10.6 &mgr;m are presented for a 2.5×5×50‐cm high‐pressure uv‐sustained discharge in a CO2:N2:He:tri‐n‐propylamine gas mixture. The spatial variation of the gain, with a resolution of a 1.5‐mm‐diam spot, is discussed. The temporal behavior of the gain is shown to be influenced by the uv‐induced photoionization, an acoustical disturbance generated by the uv source arcs, and by photoemission and collisional ionization effects near the solid electrode.

ISSN:0003-6951    

DOI:10.1063/1.1655474

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Time‐of‐flight measurements have been performed on HgI2. The electron drift mobility varies between 55 and 75 cm2/V s for fieldsE≤20 kV/cm. The plot of the electron drift velocity versusEexhibits a maximum forE∼80 kV/cm; beyond this value the differential mobility becomes negative (∼−5 cm2/V s). an electron trapping time&tgr;e+is found larger than 100 ns. Our measurements also yield estimations of the hole mobility and of the hole trapping time.

ISSN:0003-6951    

DOI:10.1063/1.1655475

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

GaAs&sngbnd;AlxGa1−xAs double‐heterostructure (DH) lasers that exhibit laser properties similar to DH lasers prepared by liquid‐phase epitaxy have been prepared by molecular‐beam epitaxy. For a structure with a 0.53‐&mgr;‐thick active layer, the as‐grown threshold current density at room temperature was 3.5×104A/cm2, but by annealing the threshold was reduced to 4.0×103A/cm2.

ISSN:0003-6951    

DOI:10.1063/1.1655476

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

A neodymium laser beam is focused in neon at low pressure. We measure the number of charges created for different laser powers. For powers corresponding to values of the electric field in the focused region greater than 3×107V/cm, there is a progressive decrease in the number of charges created.

ISSN:0003-6951    

DOI:10.1063/1.1655477

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

The anode material in an electron‐beam‐controlled gas laser strongly influences the uniformity of the sustainer discharge, because the backscattering of the beam electrons from the anode is different for different atomic numbers. As a result of switching from aluminum to, for instance, uranium, there is a 60% increase in the ionization near the anode, according to Monte Carlo computations for a typical planar laser configuration. This effect can cause a 30–60% drop in the local electric field, depending upon the field dependence of the electron‐ion recombination coefficient. As an example for studying this effect, we have considered a 150‐keV beam passing through an 0.8‐mil Ti window into a 26‐cm‐wide planar cavity containing a 3:2:1 mixture of He, CO2, and N2at 1 atm and 293 K, withEave=4.5 kV/cm. Window power loading, electron attenuation, electron energy distributions, and sustainer field distributions were calculated for the two different anode materials.

ISSN:0003-6951    

DOI:10.1063/1.1655478

出版商:AIP    

年代:1974

数据来源: AIP