摘要:

We report a novel optoacoustic (OA) cell construction which has improved small absorption measurement capability from 10−9cm−1to 10−10cm−1. The new OA cell is ideally suitable for use with planar output lasers, e.g., diode lasers. Now optoacoustic spectroscopy can be extended to include the effects of low temperatures, electric fields, and magnetic field effects.

ISSN:0003-6951    

DOI:10.1063/1.89242

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

We have constructed a simple laser‐pumped device for a visible and real‐time display of an inhomogeneous magnetic field in three dimensions. Photographic records of such displays in the form of constant‐field contours spaced 5 mG apart are presented. Our device is capable of high spatial resolution, and we have observed contour lines as sharp as 0.02 cm full width. Such real‐time high‐resolution contours cannot be obtained by conventional point‐by‐point mapping. Our device can also be used as an unconventional rf frequency spectrum analyzer.

ISSN:0003-6951    

DOI:10.1063/1.89243

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Efficient generation of tunable uv radiation to 1966 A˚ has been achieved by type‐1 frequency mixing of the outputs of the fourth harmonic of a Nd : YAG laser and a near‐infrared dye laser pumped by the second harmonic of the same Nd : YAG laser. A peak power as high as 40 kW with an average power of 2 mW was obtained at 1966 A˚.

ISSN:0003-6951    

DOI:10.1063/1.89244

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A new integrated interferometric reflector (IIR) is demonstrated in an optically pumped GaAs waveguide laser. It is shown that the laser can be wavelength tuned over 30 A˚ by very small changes in the refractive index of one IIR branch.

ISSN:0003-6951    

DOI:10.1063/1.89245

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

High‐performance backside‐illuminated photodiodes have been fabricated for the first time from InAs1−xSbx‐InAs heterostructures prepared by liquid‐phase‐epitaxy technique. The peak wavelength can be tuned compositionally from 3.1 to over 7.0 &mgr;m at 77 K. The half‐width of the spectral responses as narrow as 1760 A˚ (at 4.0 &mgr;m) have been achieved. Internal quantum efficiencies of 90% and zero‐bias‐resistance–area products of 2×107&OHgr; cm2have been obtained at 77 K.

ISSN:0003-6951    

DOI:10.1063/1.89246

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Leaky‐mode buried‐heterostructure injection lasers are fabricated and operated successfully under pulse bias at room temperature. The lasers consist of a thin active layer confined by paralleln‐ andp‐AlxGa1−xAs layers with a high mole fraction of AlAs (x=0.4) and perpendicularp−‐AlyGa1−yAs layers with a low mole fraction of AlAs (y=0.25). It is shown that most of the laser power can be coupled out into the low‐loss perpendicular layers and emitted from the end facets, resulting in highly collimated beams with a beam divergence of about 1°.

ISSN:0003-6951    

DOI:10.1063/1.89247

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A concept for a high‐density memory‐storage device is described. Information is recorded as small implantedp+(orn+) diodes, formed by a focused ion beam, on then+(orp+) surface of a large‐area diode and read by a focused electron beam. Preliminary experimental results using ion implantation through an aperture mask to simulate a focused ion beam, and a scanning electron microscope for readout, demonstrate better than 0.5‐&mgr; bit spacing. Evaluation indicates that 1010bits/cm2storage density is possible, with ≳10 Mbits/sec write/read rates, and access times <30 &mgr;sec to 1011‐bit data fields.

ISSN:0003-6951    

DOI:10.1063/1.89248

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A new acceptor level located 0.111±0.002 eV from the valence band with a peak photoionization cross section of (1.4±0.6) ×10−16cm2has been observed in indium‐doped silicon. Its presence is revealed both by the low‐temperature slope of Hall measurements versus temperature and by the spectral response of the photoconductivity. The concentration of this 0.111‐eV level is strongly correlated with the concentration of indium, suggesting that an In complex is responsible for this center.

ISSN:0003-6951    

DOI:10.1063/1.89249

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

It has been observed that an inversion layer cannot form in ap‐type silicon substrate when the Fowler‐Nordheim tunneling current into the oxide exceeds the minority generation current in the depletion layer. On the other hand, forn‐type substrates, the formation of the inversion layer is unaffected by the oxide current.

ISSN:0003-6951    

DOI:10.1063/1.89250

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Silicon films deposited on Au/Si layers at deposition temperatures at or above 380 °C are single crystal, while Si films deposited on Si with a native oxide are amorphous up to 500 °C and ordered polycrystalline above 500 °C. The initial gold (300 A˚) deposit migrates to the growing epitaxy surface where it nucleates in clusters. RBS and AES analysis indicated that 0.1 at.% gold remains distributed throughout the epitaxial film.

ISSN:0003-6951    

DOI:10.1063/1.89251

出版商:AIP    

年代:1977

数据来源: AIP