摘要:

Efficient wideband frequency conversion of the UV XeCl excimer laser wavelength has been accomplished by stimulated Raman scattering in a multimode UV silica fiber. Nine Stokes orders have been generated in the 308–350‐nm spectral region at 650‐kW input power.

ISSN:0003-6951    

DOI:10.1063/1.94422

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A technique for fabricating low‐loss (on the order of 0.1 dB/cm) integrated optical waveguides in amorphous SiO2‐based material by nitrogen ion implantation is reported. By comparing the results of nitrogen implantation and oxygen implantation in SiO2, the mechanism of waveguide formation in the nitrogen‐implanted waveguides is shown to be chemical doping effect of the nitrogen dissolved in amorphous SiO2.

ISSN:0003-6951    

DOI:10.1063/1.94423

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A new monolithic phase‐locked semiconductor laser array has been fabricated. Employing two‐level metallization, each of the eight elements in the array has a separate contact, thus making it possible to compensate for device nonuniformities and control the near‐field and far‐field patterns. Threshold currents are approximately 60 mA for each 5‐&mgr;m‐wide laser in the array. Phase locking has been observed via the narrowing of the far‐field pattern. Experimental results are compared to those obtained from the same arrays operated with all the lasers connected in parallel.

ISSN:0003-6951    

DOI:10.1063/1.94424

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Laser recording on novel optical recording media with thermal coloration is reported. The basic recording mechanism is thermally induced chemical reaction between a coloring reagent and a coupling reagent that are deposited in vacuum, separated by a light absorbing layer. Transmittance changes on a 1‐&mgr;m size recording pit have been observed by writing with a laser diode at 830 nm. This medium is colored blue, red, or black by selecting a coloring reagent layer. It is applied to multicolor recording by accumulating units of media.

ISSN:0003-6951    

DOI:10.1063/1.94425

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

We have observed enhanced analog frequency modulation in a cleaved‐coupled‐cavity (C3) laser. One diode is dc biased above threshold to produce the desired output power and the other diode, the modulator, is biased below threshold with a dc current and a small modulating current superimposed to achieve analog frequency modulation of the output beam. Comparing with direct analog frequency modulation of a conventional semiconductor laser, the C3laser has allowed us to obtain significantly larger frequency deviation with negligible spurious intensity modulation. Further, the present frequency modulation response is also much more uniform with respect to modulation frequency. In addition, this scheme is applicable to C3lasers formed from all laser structures.

ISSN:0003-6951    

DOI:10.1063/1.94426

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A novel method for broadband quasicontinuous wavelength tuning in GaAs‐GaAlAs semiconductor lasers is reported. The wavelenth tuning experiment is performed with an interferometric laser consisting of a resonator with curved and straight segments. By separately pumping different segments of the laser the output wavelength can be tuned over a wide range. The outstanding features of the device are (1) very stable single longitudinal mode and stable transverse mode operation, and (2) a wavelength tuning range of as much as 90 A˚.

ISSN:0003-6951    

DOI:10.1063/1.94427

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Passive mode locking has been achieved in a XeCl laser with the gain duration over 150 ns. The saturation characteristics of absorber dyes including BBQ, BPBD, and PTP were measured, resulting in the lowest saturation intensity of BBQ. The almost 100% modulated train of 12 pulses was achieved with the rapid pulse sharpening to the duration of ∼2 ns, when BBQ was used as a saturable absorber.

ISSN:0003-6951    

DOI:10.1063/1.94409

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A theoretical calculation of the optical properties of GaAs‐Ga1−xAlxAs superlattices is presented. The calculation includes the detailed atomic nature of the superlattice electronic states in a realistic tight‐binding model. It is found that the mixture of the bulk heavy hole and light hole states in the superlattice wave function substantially affects the optical properties.

ISSN:0003-6951    

DOI:10.1063/1.94410

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Gain on the green excimer band (&lgr;∼504 nm) of the iodine dimer has been observed in electron‐beam‐pumped mixtures of Ar (or Ne), and hydrogen iodide. A peak gain coefficient of &ggr;>1.1% cm−1is measured at 506 nm with a tunable dye laser and the full width at half‐maximum (FWHM) of the gain spectrum in Ar diluent is 13 nm. Temporally resolved gain and fluorescence measurements show that the green emission originates from an I2ion pair state other thanD′. However, strong collisional coupling between the upper states of the UV (&lgr;=342 nm) and green bands and superfluorescence on the UV band (I342∼2 MW cm−2) appear to limit the green gain coefficient to <20% of its small‐signal value. Consequently, suppression of superfluorescence on the UVD′→A′ bands of the homonuclear halogens should lead to a new family of excimer lasers with wavelengths extending from the green into the ultraviolet.

ISSN:0003-6951    

DOI:10.1063/1.94411

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Shock velocities in planar aluminum targets irradiated at 0.35‐ and 1.06‐&mgr;m laser wavelengths have been measured. Absorbed intensities of ∼1.0×1014W/cm2, produced by 700‐ps full width at half‐maximum Gaussian pulses, generated shock pressures of 1.0±0.2 and 0.6±0.2 TPa, respectively, demonstrating an enhancement of shock pressure at decreased laser wavelength.

ISSN:0003-6951    

DOI:10.1063/1.94412

出版商:AIP    

年代:1983

数据来源: AIP