摘要:

Experiments demonstrating the existence of the triatomic rare‐gas excimer Xe2F* are reported. Three‐body quenching of XeF*(B,C) yields Xe2F*, which radiates around 610 nm with a bandwidth full width at half‐maximum (FWHM) of 120 nm. The two‐body quenching constants of Xe2F* by NF3, Xe, and Ar as well as the radiative lifetime of 152 ns are determined.

ISSN:0003-6951    

DOI:10.1063/1.93549

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

This letter proposes and demonstrates the operation of a new heterojunction InGaAsP/InP laser, a double‐carrier‐confinement heterojunction (DCC‐heterojunction) laser. This laser is fabricated by incorporating ap‐InGaAsP second well layer into ap‐InP clad layer of the conventional InGaAsP/InP double‐heterojunction laser. With this laser, excellent temperature stability of threshold current [T0is 180 K in the temperature range of 20–100 °C when threshold current varies with exp(T/T0)] and high external differential quantum efficiency (more than 45% at 100 °C) were achieved. Beam divergence perpendicular to the junction plane was also much improved (less than 25°).

ISSN:0003-6951    

DOI:10.1063/1.93550

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Blumlein pulse generator has the potentiality of yielding pulse amplitude equal to the charging voltage. By applying the technique of optoelectronic switching to Blumlein pulse generator, square pulses with ultrafast rise time have been generated. In such cases, the rise time is essentially controlled by the temporal width of the picosecond laser pulse.

ISSN:0003-6951    

DOI:10.1063/1.93551

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

We report the generation of short light pulses of 23‐ps duration from an unbiased proton implanted double heterostructure cw laser by direct gain modulation. Repetition frequencies up to 10 MHz and a typical peak power of 300 mW are achieved. The time behavior of the light output is largely independent of the rise and fall time of the modulation current, since the first relaxation oscillation of the laser is utilized.

ISSN:0003-6951    

DOI:10.1063/1.93552

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Multiphoton dissociation of natural UF6was obtained by simultaneous irradiation with a CF4laser at 615.2 cm−1and a transverse, electric, atmospheric (TEA)‐CO2laser at 1073.3 cm−1using various gas pressures and laser fluences. The dissociation percentagesD235andD238of235UF6and238UF6, respectively, were determined by comparing results of an irradiated sample to those of a nonirradiated reference sample prepared under identical conditions. For the analysis we employed a simple, high‐precision nuclear technique based on gamma‐ray spectrometry. The values ofD235,D238and the resulting enrichment factorF=D235/D238were found from an analysis of the 186‐keV peak, originating in235U, and the 63‐keV peak, originating in234Th, the daughter nucleus of238U. A representative result shows a dissociation of 41±1% and235U enrichment factor of 1.049±0.016 yielded by the excitation of 0.47 Torr gas by 25 laser pulses at 20‐mJ cm−2CF4fluence and 1‐J cm−2CO2fluence.

ISSN:0003-6951    

DOI:10.1063/1.93553

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

A novel self‐heated Bi‐Sb thermocouple for far‐infrared detection has been developed. The detector is suitable for integration with monolithic antennas and imaging arrays. The device is fabricated in a single photolithography masking step using a photoresist‐bridge technique. This bridge technique has also been used to make microbolometers with lower 1/fnoise than those made by two conventional masking steps. The thermocouples have a noise equivalent power (NEP) of 7×10−10W/(&sqrt;Hz) and a 3‐dB frequency response of 150 kHz.

ISSN:0003-6951    

DOI:10.1063/1.93554

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

The performance of iron‐doped InP photoconductive detectors in the optical and x‐ray spectral regions is compared. The detectors show uniform, high cw quantum efficiency from 900 to 200 nm. Pulse response times at 193 nm are laser source limited to ⩽12 ns. The response to ∼9‐keV‐fast x‐ray pulses indicates device rise times <90 ps.

ISSN:0003-6951    

DOI:10.1063/1.93555

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Pressure applied to high performance cw 300‐K bulk‐limit (Lz∼ 600 A˚) single quantum well heterostructure AlxGa1−xAs (x∼0.28, &lgr;∼7100 A˚) laser diodes is used to simulate composition change and determine the threshold increase at shorter wavelength. Unless small quantum well sizes are employed in more sophisticated designs it is unlikely that &lgr; (for cw 300‐K operation) can be made much less than 6900 A˚.

ISSN:0003-6951    

DOI:10.1063/1.93545

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

An electron beam driven dielectric‐lined waveguide has produced 30–100 kW of coherent radiation over an octave band on the TM01mode of the waveguide. Operation of the TM02mode has been realized as well. Impedance mismatches at the ends of the liner section provide a reflected signal, which undergoes amplification during successive passes.

ISSN:0003-6951    

DOI:10.1063/1.93546

出版商:AIP    

年代:1982

数据来源: AIP

摘要:

Coherent transient Stark switching has been investigated for potential application to low‐power gigahertz modulation at 10 &mgr;m. We have observed free‐induction decay and optical nutation in ammonia on a nanosecond time scale. The results suggest that subnanosecond response should be feasible and that the heterodyne beat signal will provide improved modulation depth.

ISSN:0003-6951    

DOI:10.1063/1.93547

出版商:AIP    

年代:1982

数据来源: AIP