摘要:

Subsidiary maxima are observed in the field spectra of single mode semiconductor lasers. Measurements of their power dependence show they are linked to the relaxation resonance. We attribute these maxima to combined phase and amplitude fluctuations at the relaxation resonance. A theoretical calculation of the field spectrum using the results of a noise analysisincorporating carrier dynamics agrees very well with observations.

ISSN:0003-6951    

DOI:10.1063/1.93894

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Photodissociation of KI at 193 nm in the presence of Xe yields excimer emission in the region 410–530 nm. The intensity distribution differs dramatically from that observed following direct pumping, K (5 2 P)←K (4 2 S), the green emission being significantly weaker than that reported previously. Also, the rate of K(5 2 P) deactivation upon collision with Xe is quite inefficient,k<10−13cm3molecule−1s−1. A simple mechanism involving a curve crossing in KXe resulting in efficient quenching of K (5 2 P) to K(5 2 S) is not supported.

ISSN:0003-6951    

DOI:10.1063/1.93895

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The response times of InP photoconductors under picosecond optical illumination are observed to differ widely depending on whether the electrical bias is dc or a short pulse. The use a pulsed bias gives a slower response (>100 ps) which is more characteristic of the intrinsic material properties, than a dc bias which gives a very fast (<15 ps) response and can be attributed to imperfect contacts.

ISSN:0003-6951    

DOI:10.1063/1.93896

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Spectroscopic examination of the luminescence from SiH4and SiH4‐SiF4mixtures that are irradiated with an unfocussed, pulsed CO2infrared laser at a fluence of 0.75 J/cm2shows the emission to be due to the transitions SiH2(1B1, &ngr;′=2, 3) →SiH2(1A1, &ngr;″=1) and thus clearly demonstrates the presence of SiH2in the decomposing gas. The form of the time dependence of the emission is determined by the collisional energy pooling processes that produce highly excited SiH4molecules and does not permit an assessment of the lifetime of the1B1state of SiH2.

ISSN:0003-6951    

DOI:10.1063/1.93897

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

It is shown that metal films will absorb more infrared radiation if they are madethinner. For most metals, the maximum absorptance is obtained for films which are less than 100 A˚ in thickness. Experiments are reported here for Pt on Si, for which peak absorptance of 3.39‐&mgr;m radiation incident through the Si is found to be 0.5±0.1 for a film 80 A˚ thick.

ISSN:0003-6951    

DOI:10.1063/1.93898

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Continuous laser operation in an optically pumped Na2supersonic beam with thresholds below 1 mW and output powers in the order of 600 &mgr;W have been achieved. Laser operation independent of molecular beam parameters is investigated. This novel device holds promise for the creation of molecular beams with highly vibrationally excited molecules.

ISSN:0003-6951    

DOI:10.1063/1.93899

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Using the isolated P(33)A12one‐photon resonance in SF6the degenerate four‐wave mixing spectrum is shown to exhibit line splitting below a critical pressure. The dependence of this saturation splitting on the gas pressure and the pump intensity is quantitatively studied.

ISSN:0003-6951    

DOI:10.1063/1.93900

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Experimental evaluation of a monolithic surface acoustic wave memory correlator fabricated on a semi‐insulating GaAs wafer is reported. The correlator employed the piezoelectricity of the GaAs substrate alone without need for a ZnO overlay. A strip coupling technique was used to couple the acoustic region to the Schottky diode region which was defined by selective ion implantation. The device, with 40 wavelength long interdigital transducers, had a 3‐dB bandwidth of 5 MHz. The 0.8‐&mgr;s‐long correlation region had 500 diodes uniformly spaced at a spatial frequency of 0.5 Rayleigh wavelengths at 300 MHz. With all ports untuned, the input‐port transduction loss was 16.9 dB; an external correlation efficiency of −87 dBm was obtained.

ISSN:0003-6951    

DOI:10.1063/1.93889

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Driving pressure uniformity on the pusher surface has been significantly improved using a thick low density foam coated pellet with 120‐ps laser pulse irradiation. The pusher surface is geometrically kept at 100 &mgr;m from the laser absorption region. The hydrodynamic converging mechanism in the foam medium may be responsible for the observed smoothing.

ISSN:0003-6951    

DOI:10.1063/1.93890

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

An anomalously strong 594.5‐nm optogalvanic effect is observed in an obstructed glow discharge in 1.0 Torr of Ne occurring between plane parallel Al electrodes separated by 1.0 cm. The absolute size of a steady‐state optogalvanic effect is characterized by a dimensionless ratio of the change in power delivered to the load resistor over the absorbed laser power. A ratio of −400 for the 594.5‐nm effect is observed in the obstructed glow discharge, while ratios of −6 are typical for the 594.5‐nm effect in the positive column discharge. The 594.5‐nm effect in the obstructed glow discharge results from a laser induced depletion of metastable atoms which play an important role in electron emission from a cold cathode.

ISSN:0003-6951    

DOI:10.1063/1.93891

出版商:AIP    

年代:1983

数据来源: AIP