摘要:

Stimulated emission is reported for two polymethine dyes dissolved in glycerol when pumped by aQ‐switched ruby laser. The materials are 1, 1'‐diethyl‐2,2'‐dicarbocyanine iodide, and 1, 1'‐diethyl‐4, 4'‐carbocyanine iodide. The emission wavelength is variable over the range 750 nm to 790 nm, depending on cell length. Oscillation has been observed on both the 0–0 and 0–1 vibrational transitions.

ISSN:0003-6951    

DOI:10.1063/1.1754699

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

A laser interferometer which utilizes some Zeeman laser properties has been built and operated. The application of an axial magnetic field constrains a two‐mode 633‐nm He&sngbnd;Ne laser to oscillate simultaneously as left‐ and right‐hand circularly polarized modes at the upper and lower cavity resonances, respectively. The two modes, separated by a quarter‐wave plate and polarizers, are sent through different arms of an interferometer, and are recombined and detected with a photomultiplier. Target motions in one arm, ranging from displacements of 10−6cm at 12 kHz to 10 cm at 0.5 Hz, produced easily resolvable signals in this heterodyne device.

ISSN:0003-6951    

DOI:10.1063/1.1754700

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

A simple method of shifting the frequency of light waves with precision, based on the Doppler principle, is proposed. The proposed system consists of two reflecting mirrors. One mirror is assumed to be moving with a velocity &ngr; while the other mirror is assumed to be stationary. Practical limitations such as mirror loss, beam spread, etc., are discussed. A numerical example is also given.

ISSN:0003-6951    

DOI:10.1063/1.1754701

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

We report the direct observation of conductivity modulation by heavy‐to‐light hole transitions inp‐type germanium. The resistance of ap‐type germanium bar was modulated by microsecond pulses of 10‐&mgr; radiation from aQ‐switched CO2laser. An estimate of the fast carrier lifetime is 10−12sec. Direct observation of 20‐Mc ringing on the laser pulse is reported. The band‐to‐band type of transition permits room temperature operation.

ISSN:0003-6951    

DOI:10.1063/1.1754702

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

The luminescence of single crystals of wurtizite CdS having a strong green‐edge emission was studied at 4.2° and 77°K as a function of exciting intensity of steady 3650‐A˚ light. The typical overlapping band structure of the green‐edge emission, a zero phonon band with ∼300 cm−1phonon replica bands, was seen to shift to longer wavelengths with decreasing intensity of the exciting light. This behavior, seen in the green edge of GaP, suggests that the green edge arises from the recombination of electrons and holes trapped on distant donor and acceptor pairs.

ISSN:0003-6951    

DOI:10.1063/1.1754703

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

Bragg diffraction from longitudinal acoustic waves in tellurium is employed to modulate the 10.6‐&mgr; output of a CO2&sngbnd;He laser. Two of the photoelastic tensor components are obtained and it is shown that the efficiency with which an acoustic wave in tellurium diffracts light greatly exceeds that of any other known material.

ISSN:0003-6951    

DOI:10.1063/1.1754704

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

Two new processes for magnetoelastic or transverse to longitudinal acoustic conversion in a ferromagnet are described. Transmission of a small signal through a travelling step‐function magnetic field produces a wave with Doppler‐shifted frequency and a wave number which is approximately unchanged. By suitably adjusting the input and output conditions, various kinds of magnetoelastic and acoustic‐acoustic conversion can be achieved. Conversion of this kind also occurs when the incoming wave is subjected to a magnetic field which varies slowly in time but is uniform in space (adiabatic conversion).

ISSN:0003-6951    

DOI:10.1063/1.1754705

出版商:AIP    

年代:1966

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.1754706

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

The bleaching characteristics of saturable dyes have been studied by varying the spectral width of aQ‐switched ruby laser. Recent reports of mode selection properties of dyes used as passiveQswitches and of absorption spectra of dyes while in the bleached state have been interpreted in terms of narrow spectral saturation (``hole‐burning''). This view implies that certain dyes have inhomogeneously broadened absorption bands consisting of relatively narrow components. Our results indicate that the lower limit to the width of these components for cryptocyanine is ∼1 cm−1.

ISSN:0003-6951    

DOI:10.1063/1.1754707

出版商:AIP    

年代:1966

数据来源: AIP

摘要:

The threshold energy and the time of yielding the first laser pulse as a function of absorber concentration are experimentally determined. In cooperation with the coupled rate equations of the system, the effect of absorber concentration on the performance of a pulsed laser system is studied. The experimental data are processed in such a way to allow a direct determination of pumping dynamics through the parametersntandtp, and to measure the relative absorption cross section of cryptocyanine and ruby by observing the laser output only.

ISSN:0003-6951    

DOI:10.1063/1.1754708

出版商:AIP    

年代:1966

数据来源: AIP