摘要:

By using the linear electro‐optic effect in CdTe to mix a 10.6‐&mgr;m laser output with a pulsed (1–4‐&mgr;sec duration) microwave field produced by a magnetron, the laser’s output was shifted by 16 GHz with ≈ 27% conversion efficiency. By mechanically adjusting the microwave structure containing the CdTe and using a frequency‐swept microwave source, the shift was demonstrated to be tunable from 13.9 to 17.0 GHz.

ISSN:0003-6951    

DOI:10.1063/1.89924

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The rehydrogenation of thermally dehydrogenated amorphous silicon restores the luminescence characteristics ofa‐Si : H.

ISSN:0003-6951    

DOI:10.1063/1.89925

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Reconstructed images have been obtained by direct wave‐front conjugation in atomic sodium vapor using a cw tunable dye laser. With a pump power of only 15 mW a conversion efficiency of 0.2% has been observed.

ISSN:0003-6951    

DOI:10.1063/1.89926

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The temporal dependence of the gain recovery in a Nd‐silicate glass amplifier has been directly observed after the passage of a short intense saturating laser pulse. The gain recovery time constant measured for ED‐2 glass is 1.25±0.2 nsec. A striking polarization dependence of gain saturation recovery is observed.

ISSN:0003-6951    

DOI:10.1063/1.89927

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

We have developed a new method for determining thin‐film refractive index and thickness. In this technique, a sharply converging laser beam is coupled into the film by a prism. Dark mode lines characteristic of the waveguide structure are observed in reflection independently of absorption or scattering loss in the film. A particularly promising application is the rapid sampling of dielectric films in semiconductor technology.

ISSN:0003-6951    

DOI:10.1063/1.89928

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A simple method to characterize deep levels in high‐resistivity materials is described. Excess carriers are optically injected by pulsed light. The detrapping of these carriers leads to a transient current collected between two contacts. The signal is analyzed as in DLTS, i.e., deep level spectra are recorded during temperature cycles. Some examples of the use of this method are given.

ISSN:0003-6951    

DOI:10.1063/1.89929

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The transformation of amorphous Si layers to polycrystalline material induced byQ‐switched ruby laser single pulses of 20 and 50 nsec duration has been investigated. The analysis has been performed by transmission electron microscopy and by channeling measurements using 2.0‐MeV He+Rutherford backscattering. The average grain size of the polycrystalline layers increases with the incident energy density of the laser pulse in the range 0.6–1.7 J/cm2. A transition to single‐crystal layers is found for incident energy densities around 2.0 J/cm2. The grain size correlates with incident energy density (J/cm2) rather than incident power density (MW/cm2) for these pulse durations.

ISSN:0003-6951    

DOI:10.1063/1.89938

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A method to measure the heat transfer from a solid surface to liquid helium in the transient mode with a time resolution in the microsecond range is described. A monofilamentary NbTi/Cu compound conductor 52 &mgr;m in diameter is used as a heater by applying a current ≳Icand, via the temperature dependence ofIc, as thermometer with a response time below 10 &mgr;sec. Transient heat transfer can be described by a heat‐flow‐independent transfer coefficienth=5 W/cm2 K below a ’’take‐off’’ timet1. Att1the heat‐transfer coefficient decreases rapidly due to the onset of film boiling.t1is related to the heat flowQby the expressiont1∝Q−2.

ISSN:0003-6951    

DOI:10.1063/1.89939

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A technique for accurately measuring small superconductive inductances is presented. The inductance to be measured is inserted into a two‐junction interferometer into which control current is directly injected. The method was used to measure the penetration depth of a Pb‐In‐Au alloy film and the effect of magnetic field fringing into a narrow superconductive stripline.

ISSN:0003-6951    

DOI:10.1063/1.89940

出版商:AIP    

年代:1978

数据来源: AIP