摘要:

Internal photoemission studies of the Si‐sapphire interface ofN‐channel transistors fabricated on silicon‐on‐sapphire (SOS) indicate that the leakage current observed in such devices after exposure to ionizing radiation is due to holes trapped in the sapphire close to the silicon interface. These holes can be removed by recombination with electrons photoinjected into the sapphire from the silicon. The much smaller preirradiationN‐channel leakage cannot be removed by electron photoinjection and is therefore thought to have a different origin.

ISSN:0003-6951    

DOI:10.1063/1.88882

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Far‐infrared emission has been observed from an InSb spin‐flip Raman laser where a mode‐locked TEA CO2laser is used as the pump source. 400 &mgr;W of power are generated in 2‐nsec pulses near 100 &mgr;m. This contrasts with the usual two‐crystal scheme where one crystal is used to generate the Raman Stokes signal and a second InSb crystal is used as a mixer crystal. This experimental simplification allows for a much more direct evaluation of the usefulness of the spin‐flip Raman laser as a source of far‐infrared radiation. It is concluded that current technology permits construction of a spin‐flip Raman far‐infrared spectrometer tunable over about 60–125 cm−1.

ISSN:0003-6951    

DOI:10.1063/1.88859

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Laser action has been obtained in XeF and KrF in a transverse electric discharge powered by a fast Blumlein‐type circuit. Over‐all efficiencies of these lasers exceeded 1% for XeF and 0.3% for KrF. Maximum pulse energies of 100 mJ in XeF and 30 mJ in KrF were extracted. In XeF the peak pulse power was 25 MW while in KrF the peak pulse power was 1.5 MW.

ISSN:0003-6951    

DOI:10.1063/1.88860

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

We report high‐efficiency high‐power uv generation at 266 nm by frequency quadrupling of Nd laser using two deuterated KDP crystals. An angle‐tuned type‐II phase‐matched (eoe‐interaction) deuterated KDP crystal is used for doubling 1.064 &mgr;m and a temperature‐tuned 90° phase‐matched deuterated KDP crystal is used, for the first time, for doubling 532 nm to 266 nm. Results indicate that an average uv power of several watts with an over‐all quadrupling efficiency of around 20% is obtainable, and that high peak uv power on the order of 10 GW with an efficiency of greater than 35% can be expected for subnanosecond pulses. The high peak uv power is potentially useful for fusion studies.

ISSN:0003-6951    

DOI:10.1063/1.88861

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

We have performed numerical studies of self‐oscillation instabilities which can result from the upstream‐downstream feedback in a gas‐dynamic laser (GDL) with an unstable resonator. In this letter, which extends previous work by Dreizen and Dykhne, we show that inclusion of a simple model for CO2pumping by N2strongly damps any oscillations in the output intensity.

ISSN:0003-6951    

DOI:10.1063/1.88862

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

cw laser action has been obtained using as‐grown single‐crystal Nd:YAG fibers end‐pumped by a single high‐radiance LED. The fibers were 0.5 cm long and 80 &mgr;m in diameter, and the diameter of the LED luminous area was 85 &mgr;m. The lowest cw laser threshold was observed at a diode drive current of 45 mA.

ISSN:0003-6951    

DOI:10.1063/1.88863

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The first CO2laser enrichment of deuterium in the gaseous phase of formaldehyde is reported. Irradition with pulses from a ∼20‐MW CO2TEA laser focused strongly onto the sample yields highly efficient selective photodissociation of the formaldehyde molecule. A deuterium enrichment factor of approximately 40 is found for formaldehyde gas at an initial pressure of 20 Torr, after irradiation with 300 laser pulses.

ISSN:0003-6951    

DOI:10.1063/1.88865

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

We report the successful passive mode locking of a single‐line unstable‐cavity HF laser. Saturable absorption for the passive mode‐locking process was provided by low‐pressure HF gas in a separate cell internal to the optical cavity. Experimental results are consistent with mode‐locking theory and behavior in other systems.

ISSN:0003-6951    

DOI:10.1063/1.88866

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Step‐tunable infrared radiation in the 12‐&mgr;m region can be generated by two‐step noncollinear difference‐frequency mixing of CO2laser beams in GaAs at liquid‐helium temperature. With 3‐MW peak input power from each of the two CO2lasers operating at 9.6 and 10.6 &mgr;m, peak output power of ∼4 kW was obtained at 11.8 &mgr;m.

ISSN:0003-6951    

DOI:10.1063/1.88867

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The Schottky barriers formed onn‐ZnS andn‐ZnSe by polymeric sulfur nitride have been compared to barriers formed by Au. Barrier energies as determined by photoresponse, current‐voltage, and capacitance‐voltage methods show that (SN)xis approximately 1.0 eV higher than Au onn‐ZnS and 0.3–0.4 eV higher than Au onn‐ZnSe. We believe that this is the first report of any metallic contact more electronegative than Au.

ISSN:0003-6951    

DOI:10.1063/1.88868

出版商:AIP    

年代:1976

数据来源: AIP