摘要:

Rotationally relaxed, grating tuned laser oscillations are obtained in the frequency range 500–562 cm−1via the optical pumping of C2D2/He mixtures with a transverse, electric, atmospheric (TEA) CO2laser. StrongQ‐branch oscillations at 530.8 cm−1are also reported.

ISSN:0003-6951    

DOI:10.1063/1.93435

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Javan and coworkers have reported pure rotational laser oscillation from OH and OD in a pulsed discharge through H2‐O2‐SF6mixtures. The pumping mechanism was not established, but it was thought at the time to be chemical. The intensity distribution can be understood as resulting from the electronic to rotational transfer of 13 200 cm−1from O2(1&Sgr;+g) to ground vibrational state OH(2&Pgr;) leaving the O2in its ground3&Sgr;−gstate. Unexcited OH would be formed from either the reaction O+H2= OH+H or H+O2= OH+O. Nothing can be said about the efficiency of thisE‐Rtransfer compared toE‐V; however,E‐Rappears to be a new mechanism for pumping diatomic, pure rotational inversions. The full explanation of this laser also demands the conclusion that SF6, like the rare gases, can serve as a collision partner inducing intramolecularV‐Rtransition in OH.

ISSN:0003-6951    

DOI:10.1063/1.93443

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

A novel semiconductor laser employing a cavity structure of the open ended Michelson interferometer is studied. The interference effect is used to select and stabilize the longitudinal mode of the laser. Experimental results showed that lasing action is observed only at the few coincident resonant modes that do not suffer any interference loss. Hence the operating wavelength is primarily determined by the cavity dimensions. The laser showed a change of 0.667 A˚/ °C in its lasing wavelength with temperature, a considerable improvement over the conventional Fabry–Perot lasers.

ISSN:0003-6951    

DOI:10.1063/1.93444

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

New laser lines at 3.71 and 3.84 &mgr;m in hydrogen and lines at 4.52, 4.60, and 4.71 &mgr;m in deuterium excited by a pulsed electrical discharge have been obtained. The lines in hydrogen are assigned to thea 3&Sgr;+g → c 3&Pgr;utriplet band, but the lines in deuterium have not yet been assigned. Direct electronic excitation from the ground state to thea 3&Sgr;+gstate is believed to be the excitation mechanism, and indicates that an excimer‐type laser from thea 3&Sgr;+gupper state to the dissociativeb 3&Sgr;+ustate may be possible.

ISSN:0003-6951    

DOI:10.1063/1.93445

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Measurements have been made of the vibrational excitation of HCl under typicale‐beam XeCl laser conditions. The results indicate less than 10% excitation to the first vibrational level. This is too small to yield the tenfold enhancement of dissociative electron attachment predicted by existing XeCl laser models.

ISSN:0003-6951    

DOI:10.1063/1.93446

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Operation of a coupled multiple stripe quantum well injection laser array is described. The device emits up to 400 mW of continuous output power and 2.1 W of peak pulsed (75 ns) output power from an uncoated mirror facet. Its far‐field pattern is invariant to over three times threshold, and over 140 mW cw are coupled into a 100‐&mgr;m core 0.3‐numerical aperture (N.A.) optical fiber.

ISSN:0003-6951    

DOI:10.1063/1.93447

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Theoretically estimated limiting electron densities for plasma‐recombination lasers are shown to agree with experimentally measured values over a wavelength variation of nearly one decade. Radiation trapping is found not to restrict the electron densities in recombination lasers that operate at wavelengths longer than about 100 nm. For wavelengths shorter than 150 nm predicted specific output energies for plasma‐recombination lasers may exceed those of excimer lasers.

ISSN:0003-6951    

DOI:10.1063/1.93448

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Experimental investigation was carried out to study the transient regimes during the buildup and decay of the active mode‐locked state in a laser diode. The mode locking was achieved through a sinusoidal modulation of the diode current with the laser in an external cavity. The pulse shape evolution and the time constants for the buildup and decay were determined.

ISSN:0003-6951    

DOI:10.1063/1.93449

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

A very low threshold GaAlAs buried heterostructure laser has been monolithically integrated with a recessed structure metal‐semiconductor field‐effect transistor on a semi‐insulating substrate. At cw operation, the device has a direct modulation bandwidth of at least 4 GHz.

ISSN:0003-6951    

DOI:10.1063/1.93425

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

The characteristics of oxide‐defined, narrow‐stripe large‐optical‐cavity (LOC) AlGaAs lasers are described. Compared with regular narrow‐stripe double heterostructure (DH) lasers, the LOC version exhibits more narrowing of the near‐field and far‐field distributions, higher astigmatism, higher differential quantum efficiency, and higher incidence of sustained pulsations. We have found that these phenomena can be explained in terms of the formation of a thermal waveguide. There is often a striking similarity in characteristics of narrow‐stripe LOC and degraded narrow‐ stripe DH lasers. We suggest that a thermal waveguiding effect is an important factor in determining the behavior of degraded semiconductor lasers.

ISSN:0003-6951    

DOI:10.1063/1.93426

出版商:AIP    

年代:1982

数据来源: AIP