摘要:

Liquid‐phase epitaxy of doped Li1−xNaxNbO3films on LiNbO3has been performed. Sodium‐doped films show a 30% reduction in the temperature coefficient of surface acoustic wave velocity.

ISSN:0003-6951    

DOI:10.1063/1.89988

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A simple method is described for generation and detection of surface waves in nonpiezoelectric dielectrics due to creation of a space‐charge region and a polarized surface layer under the interdigital electrodes. By direct evaporation of electrodes onto the surface of nonpiezoelectric materials, and without use of dc bias, Rayleigh waves with a signal‐to‐noise ratio as high as 60 dB have been generated. We have demonstrated the method on cubic KTaO3and cubic BaTiO3. Additional application of dc bias further enhances the signal which is retained even after removal of the bias. High sensitivity to band‐gap illumination is observed, allowing a direct determination of the band gap.

ISSN:0003-6951    

DOI:10.1063/1.89989

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A new theory of coherent mode interactions in integrated optics is described with particular reference to light scattering by surface waves. This analysis is characterized by exact solutions to polarization‐driven wave equations and electromagnetic boundary conditions.

ISSN:0003-6951    

DOI:10.1063/1.89990

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Surface acoustic wave properties of fresnoite have been calculated from bulk material parameters and have been measured along several orientations on samples cut from Czochralski‐grown crystals. Favorable properties are measured for thez‐cutx‐propagating wave: the coupling coefficientk2is 0.016±0.003, the velocity is 2678 m/sec, and the temperature coefficient of delay is 51×10−6/ °C. These values, as well as those measured for the much lower couplingx‐zandx‐ysurface waves, are in agreement with calculations. The calculations also predict that, for surface waves propagating in thexdirection on a surface whose normal is at 45° tozandyaxes, the coupling coefficient is 10% higher than calculated for the abovez‐xcase.

ISSN:0003-6951    

DOI:10.1063/1.89991

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The high‐intensity transmission characteristics of CH3CHF2and CHFCHF were investigated in the intensity range of 5×106to 5×108W/cm2for various lines of the CO2lasing branches. For similar gas pressures, the ratio of small to large intensity absorption coefficients is relatively constant at various CO2lasing lines. The ratio of ∼6 measured for CH3CHF2at 10.6 &mgr;m renders this molecule a good candidate for CO2amplifier gain isolation.

ISSN:0003-6951    

DOI:10.1063/1.89992

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Measurements are reported of the polarization and angular dependence of the amplitude and ’’temperature’’ of high‐energy bremsstrahlung emission from planar copper targets irradiated with 25‐psec neodymium laser pulses at 5±2×1014W/cm2. A resonance in the emission is observed forp‐polarized incident radiation at an angle of incidence of 25°. The results indicate the presence of plasma density scale lengths of about 1 &mgr;m and 17% absorption due to the resonance absorption mechanism.

ISSN:0003-6951    

DOI:10.1063/1.89993

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The pohotoionization of uranium atoms by the 3511‐ and 3345‐A˚ uv lines from an argon ion laser was observed and attributed to resonant two‐photon ionization. Application to uranium laser isotope separation is discussed.

ISSN:0003-6951    

DOI:10.1063/1.89994

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

We find field reversals up to four times the initial field and changes in the magnetic field on the axis of symmetry of 6 kG when a rotating electron beam is injected through a cusp into an initially neutral gas. The change in magnetic field on the axis was found to be independent of the magnetic field. This is shown to be consistent with measurements that the cusp transmission coefficient times the ratio of the azimuthal velocity (V&Vthgr;) to the axial velocity (Vz) is independent of magnetic field.

ISSN:0003-6951    

DOI:10.1063/1.89987

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A shock wave in fusion fuel filled in a glass microballoon target was directly observed. The shock speed and the width of the shock front were 5×107cm/s and a few &mgr;m, respectively, which are in good agreement with the shock‐tube theory.

ISSN:0003-6951    

DOI:10.1063/1.89995

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A neutron activation technique has been used to analyze the gallium content in SiO2films deposited onn‐type GaAs. Gallium was observed in the SiO2films after annealing at temperatures between 730 and 940 °C. It is found that the surface of GaAs reacts with the H2O in the SiO2films and/or ambient gas via pinholes at these high temperatures. The reaction is influenced by the partial pressure of water in the ambient gas.

ISSN:0003-6951    

DOI:10.1063/1.89996

出版商:AIP    

年代:1978

数据来源: AIP