摘要:

Convolution of two acoustic surface waves (ASW) has been obtained by the acousto‐optical diffraction of an optical wave in an As2S3waveguide. A simple theory is presented to show the convolution process. Experimentally, very high acousto‐optical diffraction efficiency (93% at 3 mW of acoustic power) has been observed in the As2S3waveguide. A triangular pulse was observed on the oscilloscope through an optical heterodyne detector when two rectangular ASW pulses were convolved with each other.

ISSN:0003-6951    

DOI:10.1063/1.88672

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

A number of filter structures utilizing acoustic surface waveguides and periodic arrays of reflecting strips to form multimoded resonant configurations are described. The devices described are analogous to the monolithic crystal filter in that an array of acoustically coupled resonators is obtained from a structure placed on a single substrate. The coupling between resonators is described in terms of trapped energy modes of the surface‐waveguiding structures.

ISSN:0003-6951    

DOI:10.1063/1.88673

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

GaAs reflection photocathodes grown by vapor‐phase epitaxy using trimethyl gallium and arsine have been activated to a maximum sensitivity of 1150 &mgr;A 1m−1. The material is of high quality and has diffusion lengths and surface escape probabilities which are comparable with those measured for liquid‐phase epitaxial material.

ISSN:0003-6951    

DOI:10.1063/1.88674

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Measurements have been made with subnanosecond resolution of the azimuthal magnetic field spontaneously associated with plasmas produced by high‐intensity (1012–1014W/cm2) 1‐nsec‐duration CO2laser pulses. In addition to a distinct dependence on background argon gas pressure, it is found that the magnetic field displays a 1/r2radial dependence, and its onset is synchronous with the initial formation of the plasma.

ISSN:0003-6951    

DOI:10.1063/1.88675

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Stark‐tuned level anticrossing between hyperfine levels was observed in the nonlinear absorption of the CD3I &ngr;2 QP(4,1) transition by using the CO2laser line. Good agreement between the theoretical and the observed linewidth was obtained.

ISSN:0003-6951    

DOI:10.1063/1.88676

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The laser heating of an initially uniform plasma column has been modeled in a self‐consistent way, including the effects of medium magnetohydrodynamics and refraction and diffraction of the laser light. The results show that a portion of the pulse can become trapped, leading to a pattern of alternate focusing and defocusing of the beam.

ISSN:0003-6951    

DOI:10.1063/1.88684

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

A new scheme for tuning a planar waveguide dye laser is presented. Because of the high gain produced in the waveguide structure, a high‐dispersion slit‐grating arrangement can be used as a feedback element of the laser. Output energy of a few tens of mJ, which corresponded to the saturated output of the amplifier, was obtained within a 2‐GHz bandwidth. A very stable and repeatable output frequency was observed. The device demonstrates that, as long as the waveguide overcomes gain and refractive index inhomogeneities, a much higher energy output can be expected from scaled‐up devices.

ISSN:0003-6951    

DOI:10.1063/1.88685

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Coupling between planar 7059‐glass and CdS optical waveguides has been demonstrated. The CdS–7059‐glass films form part of a multilayer electro‐optic phase modulator, the first such device to be reported which uses polycrystalline films evaporated on to amorphous substrates. The behavior of the modulator structure is completely accounted for when dielectric relaxation effects in CdS films are considered.

ISSN:0003-6951    

DOI:10.1063/1.88686

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

GaP diodes containing indium and oxygen emitted intense green light (2.23 eV) with weak red light (1.77 eV) at room temperature. The green light emission was enhanced by In and the spectral measurements revealed the green light to be due to the simultaneous annihilation of a free exciton and a LA phonon. The diode had ap‐i‐nstructure, and the green light was emitted from the intrinsic region which was formed by oxygen deep donors. At appropriate oxygen concentrations, diodes which emit only green light were fabricated successfully.

ISSN:0003-6951    

DOI:10.1063/1.88687

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Radiation from a cw CO2laser is used to separate SF6molecules from helium molecules in a bulk mixture of each, by resonant radiation pressure. These experimental results demonstrate that selective absorption of radiation can cause physical separations of molecules within a diffusion‐limited geometry.

ISSN:0003-6951    

DOI:10.1063/1.88663

出版商:AIP    

年代:1976

数据来源: AIP