摘要:

Measurements of the effects of a weak axial magnetic field on the output energy of a CuCl double‐pulse laser have been made. It was anticipated that the application of a weak 290‐G magnetic field could serve to stabilize the discharge in the laser tube and to, therefore, increase the output energy of the laser. Such increases were observed for large values of the delay time between the two successive electrical discharges but not for the optimum delay of 175 &mgr;sec, and a reduction in the output of the laser occurs for very small time delays. The mechanism by which the magnetic field enhances (or reduces) the laser output is not presently well understood but two alternatives are discussed.

ISSN:0021-8979    

DOI:10.1063/1.324358

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A discharge‐pumped KrF excimer laser, utilizing a rapid recirculation of atmospheric‐pressure gas, has generated 10 W of average output power at a pulse repetition rate of 1 kHz. The usual spark gap was replaced with a hydrogen thyratron for the switch in the pulse‐forming network, and a corona discharge was used as the source for discharge preionization. Operating at 30 psi (absolute) and at a pulse rate of 2 Hz, a similar device has generated output pulse energies of 100 mJ at 1&percent; efficiency and 80 mJ at 1.6&percent; efficiency.

ISSN:0021-8979    

DOI:10.1063/1.324359

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Radio‐frequency emission from laser‐produced plasmas has been observed from 1 to 330 MHz. The emission is found to be dependent on plasma and vacuum‐chamber conditions. The low‐frequency (1 MHz) oscillations appear characteristic of large‐scale charge oscillations in the plasma.

ISSN:0021-8979    

DOI:10.1063/1.324360

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Estimates of a plasma temperature, electrical conductivity, and torch efficiency have been made from simple measurements made on the plasma and on the rf supply. Measurements were made with the aid of a simple magnetic probe and a pickup coil. Estimates are also made of the heating‐coil constants.

ISSN:0021-8979    

DOI:10.1063/1.324361

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The addition of glass formers, B and P, raises not only the shear stiffness but also the tensile yield strain (&egr;y) of Fe‐ and Co‐based glasses. &egr;yincreases by a factor of 2 from 1.23×10−2for Pt–Ni–P glasses to 2.45×10−2for Fe–B glasses as the Poisson’s ratio decreases from 0.42 to 0.32. The Vickers hardness of a Fe75B25glass attains 1300 kg/mm2which is the highest value reported for metallic glasses. The directionality of interatomic forces either due to atomic ordering ors‐dhybrid bonding in transition metals is proposed to be responsible for this behavior.

ISSN:0021-8979    

DOI:10.1063/1.324362

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

It is suggested that a temperature‐dependent gap in Gd‐doped EuSe, similar to a suggestion of Oliver for EuO, will reconcile RKKY magnetism and localized magnetic polarons as dominant phenomena.

ISSN:0021-8979    

DOI:10.1063/1.324363

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Deep trapping centers inn‐type InP samples grown by the liquid‐encapsulated Czochralski, liquid‐phase‐epitaxial, and vapor‐phase‐epitaxial processes have been studied by photocapacitance techniques. Photocapacitance effects for Schottky barriers formed on these samples indicate four levels at 0.58, 0.78, 0.89, and 1.15 eV below the conduction band. Estimated trap concentration in various samples range from low‐1014cm−3to the high‐1012cm−3. The broad increase in photocapacitance near 1.15 eV for all the samples may be associated with an intrinsic defect or phosphorus vacancy/impurity complexes. This result is consistent with the broadband present between 1.08 and 1.25 eV in photoluminescence experiments. The comparison between O2‐doped and undoped VPE samples suggests the presence of oxygen located at about 0.78 eV below the conduction band in VPE material.

ISSN:0021-8979    

DOI:10.1063/1.324364

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Longitudinal and transverse magnetoresistances have been measured in single‐crystalp‐type PbTe of hole concentrationp=1.3×1019cm−3at 4.2 K up to a magnetic field of 68 kG. These magnetoresistances vary linearly with magnetic field. The effective mass anisotropyKof the crystal has been estimated from the magnetoresistance measurements in the classical field region, using the theory of Gold and Roth. The value ofKis 3.5.

ISSN:0021-8979    

DOI:10.1063/1.324365

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

We have analyzed the operation of a UHF biased SQUID circuit in which it is possible to achieve near‐perfect coupling of all the available SQUID signal power to a room‐temperature amplifier. An experimental version of this circuit has attained a measured intrinsic energy resolution of 5×10−30J H−1z.

ISSN:0021-8979    

DOI:10.1063/1.324366

出版商:AIP    

年代:1978

数据来源: AIP