摘要:

An experimental study is made of filamentary impact ionization breakdown observed in germanium doped with both group III and group V elements at liquid helium temperature.The approximate size of the filament at various current values after ionization is estimated from the measurement of voltage‐current characteristics of small cross section bars with high current pulses. Measurements are also made with cylindrical ``tecnetron'' structures in which the conduction channel can be reduced to very small areas by reverse bias of a ring‐shapedp‐njunction alloyed around a small cylindrical bar. Results of the two experiments are consistent. Near the lowest current value at which ionization can be sustained (about 40 &mgr;a), the approximate filament diameter is 10−3cm.

ISSN:0021-8979    

DOI:10.1063/1.1777205

出版商:AIP    

年代:1962

数据来源: AIP

摘要:

General expressions are developed for the shielding factors of concentric spherical shells of linear isotropic magnetic material. Approximate results are given for shells of highly permeable material which are thin compared to their radii.

ISSN:0021-8979    

DOI:10.1063/1.1777151

出版商:AIP    

年代:1962

数据来源: AIP

摘要:

This report presents a survey of domain structures observed on some lead films under various conditions of applied magnetic field, made visible using the magneto‐optic technique. Fields due to a current are also observed. The static appearance and the dynamic behavior of the patterns are similar to the appearance and the behavior observed earlier in bulk samples of ``hard'' superconductors.

ISSN:0021-8979    

DOI:10.1063/1.1777152

出版商:AIP    

年代:1962

数据来源: AIP

摘要:

Single crystals of CdTe have been grown from the vapor. Crystals grown by the methods described grew either as hexagonal rods or dodecahedra. Both types of crystals have been identified, by back‐reflection x‐ray photographs, as cubic CdTe. The exhagonal rods have extensive micro‐twinning.

ISSN:0021-8979    

DOI:10.1063/1.1777153

出版商:AIP    

年代:1962

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1777154

出版商:AIP    

年代:1962

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1777155

出版商:AIP    

年代:1962

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1777157

出版商:AIP    

年代:1962

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1777158

出版商:AIP    

年代:1962

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1777159

出版商:AIP    

年代:1962

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1777160

出版商:AIP    

年代:1962

数据来源: AIP