摘要:

An abrupt reduction in the rate of growth of the spontaneous emission has been observed to occur at the lasing threshold of stripe‐geometry double‐heterostructure injection lasers. The observations are contrary to a previously published result of Sommers and imply that increases in the quasi‐Fermi level separation with current are significantly reduced at the lasing threshold in agreement with present theoretical predictions.

ISSN:0003-6951    

DOI:10.1063/1.1654287

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

The amount of Cs&sngbnd;O low‐work‐function surface material required to optimize the photoresponse of InAs0.4P0.6depends upon the wavelength at which the response is to be maximized. It is shown that the optimum thickness increases exponentially with wavelength.

ISSN:0003-6951    

DOI:10.1063/1.1654288

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Some unique physical property changes related with the TiNi martensitic transition, such as ``memory'' effect, have been known for some time. In this letter we report some additional observations which are of interest and are related to the TiNi transition.

ISSN:0003-6951    

DOI:10.1063/1.1654289

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Many dislocations were found to be induced when GaAs chips for Gunn diodes were mounted on a heat sinking stud by a thermocompression bonding method. By introducing dislocations into epitaxial GaAs with a bending method, dislocations were confirmed to behave as acceptors in GaAs. Degradation or increase of the low field resistance of a Gunn diode by thermocompression bonding is considered to be due to induced dislocations.

ISSN:0003-6951    

DOI:10.1063/1.1654290

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

A monochromatic source may be used to excite individual isotopic lines in a well‐resolved absorption spectrum for which the upper state is predissociated. Isotopic enrichment is thus achieved in the dissociation products, which may be stable molecules or may be chemically trapped if they are reactive. As an example, isotopic separation of hydrogen and deuterium is performed by exciting formaldehyde with a frequency‐doubled ruby laser.

ISSN:0003-6951    

DOI:10.1063/1.1654291

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

An exploratory field‐ion‐microscope study of the interface between solid and liquid metals in vacuum is reported using a Ga&sngbnd;In&sngbnd;Sn alloy as the liquid metal. The result with tungsten was no surface atom rearrangement at the interface; with molybdenum, the formation of an alloy of unidentified crystal structure; with iridium, no alloy formation but dissolution of a part of the tip; and with platinum, complete dissolution of the tip.

ISSN:0003-6951    

DOI:10.1063/1.1654292

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

A CO2gas‐dynamic laser (GDL) was operated over a range of reservoir pressures and temperatures, test‐gas mixtures, and nozzle geometries. A significant result is the dominant influence of nozzle geometry on laser power at high pressure. Results show that high reservoir pressure can be effectively utilized if nozzle geometry is chosen to efficiently freeze the test gas. Maximum power density with the least efficient nozzle was 3.3 W/cm3of optical cavity volume, whereas 83.3 W/cm3was attained with the most efficient nozzle.

ISSN:0003-6951    

DOI:10.1063/1.1654293

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Measurements of the magnetic fields from skeletal muscles, called magnetomyograms (MMG's), have been taken in a heavily shielded room with a superconducting magnetometer. These magnetic fields appear to be produced by the same currents in the volume conductor, associated with muscle action potentials, which also produce the surface electromyogram (EMG). Unlike the EMG, however, the MMG can readily detect slowly changing or direct currents. The MMG's, which were taken at locations near the elbow and the palm of the hand, are shown along with their frequency spectra.

ISSN:0003-6951    

DOI:10.1063/1.1654294

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Effects of a spatial distribution of deep centers on the junction capacitance are reported for the first time. It is shown that the spatial distribution of deep centers can be calculated from capacitance data measured by both the capacitance‐voltage method and the Copeland method, if their energy level is known or assumed. The theory is examined with the experiment on siliconp+njunctions irradiated with 300‐kV protons. The analysis yields a value 0.40 eV below conduction band for the energy level of radiation‐induced defects, as well as a distribution of the defects with depth.

ISSN:0003-6951    

DOI:10.1063/1.1654295

出版商:AIP    

年代:1972

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.1654296

出版商:AIP    

年代:1972

数据来源: AIP