摘要:

Postgrowth annealing has been found to give layers of PbTe and Pb1−xSnxTe (withx≈ 0.2) with much larger low‐temperature Hall mobilities than as‐grown layers. At temperatures down to about 50 °K the Hall mobilities are close to those of good bulk crystals. Below 50 °K there is a tendency to saturation at values greater than 105cm2V−1sec−1. Structural studies indicate that both as‐grown and annealed specimens are single crystals with about the same concentration of low‐angle grain boundaries as the BaF2substrates. It is suggested that the annealing process removes an excess of native defects.

ISSN:0021-8979    

DOI:10.1063/1.1659813

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

Magnetostriction constants of MnxFe3−xO4at room temperature are reported and related to the cation distribution in these spinels. Octahedral Fe2+ions give a positive contribution to &lgr;111. The contribution to &lgr;100of octahedral Mn3+ions is negative in this system and is not a linear function of the Mn3+concentration, which may be caused by local stresses in the crystal.

ISSN:0021-8979    

DOI:10.1063/1.1659814

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

Mechanically stable, room‐temperature—helium‐temperature‐cyclable insulated double and single point contacts have been obtained by use of an insulating glass with thermal expansion matching that of the niobium superconductor. When two of these contacts are connected in parallel, the resultant device works quite well as a cyclable dc‐biased magnetometer.

ISSN:0021-8979    

DOI:10.1063/1.1659815

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

The power efficiency of ZnS : Tm under cathode‐ray excitation was determined as 0.216 W/W, the highest yet reported for any rare‐earth‐activated phosphor. The unusual power distrition among the three emission manifolds concentrates the major portion of the luminosity in a single narrow blue band, yielding an unusual, highly saturated, nearly monochromatic, efficient source.

ISSN:0021-8979    

DOI:10.1063/1.1659816

出版商:AIP    

年代:1971

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1659818

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

A laser‐isolator device capable of protectingQ‐switched lasers from target backscatter has been designed and tested. The technique is readily applicable to lasers of any aperture.

ISSN:0021-8979    

DOI:10.1063/1.1659819

出版商:AIP    

年代:1971

数据来源: AIP