Volume 43, Issue 12, 01 December 1972
Index of content:
43(1972); http://dx.doi.org/10.1063/1.1661097View Description Hide Description
The diffraction‐contrast characteristics of twinning partials have been examined for | g · bp | = 1/3 and 2/3, where g is the operating reflection and bp is the Burgers vector of the partial. The results can be rationalized in terms of the intensity profiles computed by Tunstall and Goodhew for the partials bounding overlapping stacking faults. Further, when | g · bp | is 2/3, the interface dislocations exhibit, for the same g, variations in their contrast. Arguments for rationalizing these observations are developed. A simple analytical procedure for differentiating between twins and complementary twins is also proposed
Reflections from a plasma sphere and relationship between plasma frequency and the classical electron radius43(1972); http://dx.doi.org/10.1063/1.1661099View Description Hide Description
Plasma frequency, ω p , may be expressed in terms of the classical electron radius re by the relationship: . The use of this relationship permits the reflection cross section of a spherical cluster of electrons to be expressed in terms of electron radius, when this is convenient, or alternately, in terms of macroscopic quantities such as plasma frequency and the radius of the electron cluster.
Observation of the amorphous‐crystalline phase transition in the Ovonic semiconducting glass Te81Ge15As4 by the Mössbauer effect in Te125 and I12943(1972); http://dx.doi.org/10.1063/1.1661100View Description Hide Description
Mössbauer spectra obtained with absorbers of and a ZnTe125m source indicate that tellurium atoms are in an environment similar to that in telluriummetal. These spectra as well as those obtained with sources of and a CuI129 absorber indicate that the amorphous phase has a higher charge asymmetry than the crystalline phase which is consistent with the concept of ``dangling'' chemical bonds. Because of the great difference in the I129spectra of the amorphous and crystalline phases it appears of interest to investigate Ovonic devices prepared with Te129m in order to see if voltage‐dependent phenomena can be observed in the I129 Mössbauer spectra.
43(1972); http://dx.doi.org/10.1063/1.1661101View Description Hide Description
The condition for zero temperature sensitivity of bubble diameter in some uniaxial magnetic materials is obtained in terms of the material parameters. The ratio of the fractional changes in wall energy density and saturation magnetization which gives zero temperature sensitivity of bubble diameter is plotted as a function of plate thickness and bubble diameter. The resulting curves can be used in designing bubble devices having fixed bubble sizes.