摘要:

A miniature cw chemical laser is described which can serve as a convenient multiline source in the ir. It employs condensible carrier gases with cryosorption pumping only (thus no moving parts) to deliver 300 and 200 mW, respectively, of HF and HCl radiation. Five laser reactions with a total of nine lines each of HCl and HF in the regions 2.6–3.0 and 3.6–4.0 &mgr;m, respectively, have been observed. For the F+CH4reaction (using SF6as the F atom source and carrier gas) most of the power extracted is in theP1(4) line. For the Cl+HBr reaction, the full laser power is emitted in theP1(5) line.

ISSN:0003-6951    

DOI:10.1063/1.90187

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A damped oscillation following a stepwise modulation of an intracavity saturable absorber has been observed in the output power of an infrared CO2and N2O laser. A high frequency of oscillation (∼100 kHz) and a large damping rate were observed for a high laser power and, when the laser power was lowered, both were reduced with the damping rate becoming zero as the laser started passiveQswitching. The smooth variation of the characteristics into the passiveQ‐switching region indicates that the damped oscillation is caused by the same mechanism which causes the passiveQswitching, that is, the exchange of radiative energy between the laser gain medium and the saturable absorber. For a laser operating in the low‐power regime, a narrow resonance has been observed in the laser modulation depth when the frequency of the stepwise modulation was varied continuously from 10 to 100 kHz. This resonance can be used effectively for increasing the sensitivity of intracavity laser spectroscopic experiments.

ISSN:0003-6951    

DOI:10.1063/1.90162

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

For isotope enrichment of chlorine, Cl2was excited by a 488‐nm line of the Ar ion laser and reacted with tetrachloroethylene. It was found that the reaction rate was limited to the excitation rate of Cl2by the laser. The enrichment factor of37Cl in residual Cl2increased linearly with the irradiation time and the result agreed with the approximate relation derived from the reaction rate. The enrichment factor of 1.17 was obtained after 120 min irradiation at the laser power of 180 mW.

ISSN:0003-6951    

DOI:10.1063/1.90188

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Resonantly enhanced three‐photon ionization spectroscopy is employed for the detection of ground‐state atomic hydrogen and deuterium. Concentrations as low as 4×109atoms/cm3in the presence of 1017atoms/cm3of buffer gas are detected with an implicit time resolution of less than 10 nsec. A useful dynamic range of at least 4×104is demonstrated and saturation of the ionization in a 2×10−4‐cm3focal volume is observed. The presence of H can easily be distinguished from that of D and the three‐dimensional spatial distribution of H or D can be determined.

ISSN:0003-6951    

DOI:10.1063/1.90163

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Zinc chloride glass is a potentially useful medium for ultralow‐loss (∼1 dB/103km) optical fibers for wavelengths in the 3.5–4‐&mgr;m region. In this region, intrinsic absorption, scatter, and material dispersion are all expected to be small, and the common fully oxidized transition metal impurities and H2O should exhibit extremely weak absorption as well.

ISSN:0003-6951    

DOI:10.1063/1.90189

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Powerful laser output was observed at 381 nm from electron‐beam‐pumped ternary mixtures of argon‐nitrogen and 2,2′‐p‐phenylinebis(5‐phenyloxazole) (POPOP) dye vapor. The injection of the subthreshold 380.5‐nm N2line into the electrically excited gain profile of POPOP vapor has been identified as a pumping mechanism.

ISSN:0003-6951    

DOI:10.1063/1.90190

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The attenuation coefficient and coupling loss were measured in single‐mode Ti‐diffused LiNbO3waveguides with cleaved end faces. Coplanar electrodes increase the attenuation substantially but a dielectric buffer layer can eliminate most of the electrode absorption.

ISSN:0003-6951    

DOI:10.1063/1.90191

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The XeF* and F* sidelight emissions, the small‐signal gain, and the transient plasma absorption near the laser wavelength have been measured from a XeF self‐sustained discharge laser. We conclude that the production of XeF* in its lower vibrational levels requires collisions with He atoms, and that XeF* decays predominantly by radiative processes and He quenching. The transient absorption at the laser wavelength, believed to be due to F−, F*, F*2, and Xe+2, can be as large as ∼1–2%/cm at small‐signal gains of ∼8%/cm.

ISSN:0003-6951    

DOI:10.1063/1.90146

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Room‐temperature operation of new type of Ga1−xAlxAs‐GaAs laser employing distributed Bragg reflectors for optical and carrier confinement has been demonstrated. These distributed‐Bragg‐confinement lasers are grown by metalorganic chemical vapor deposition and exhibit low‐threshold current densities and small angular beam divergence.

ISSN:0003-6951    

DOI:10.1063/1.90147

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

We report a novel technique to determine the index change in Li2O in‐diffused surface layer in LiNbO3by observing the cutoff angle of the extraordinary substrated mode as it refracts through the surface‐layer–substrate interface. Surface‐layer index changes from 10−4to 10−2were measured in various samples which received compensation treatments for times of 10 min to 6 h, primarily in LiNbO3powder. We also report the successful compensation of nearly single‐mode Ti : LiNbO3channel waveguides.

ISSN:0003-6951    

DOI:10.1063/1.90149

出版商:AIP    

年代:1978

数据来源: AIP