摘要:

The floating crucible method for growing single crystals is described. This method, a simple modification of the Czochralski technique, permits the growing of large germanium single crystals of uniform resistivity. By growing the crystal from an inner crucible floating in the germanium melt, the condition of constant liquid volume in the inner crucible is achieved and the concentration gradient characteristic of crystals grown by the Czochralski method is elminated. Earlier determinations of the distribution coefficients of some doping impurities in germanium have been verified. The density of liquid germanium at the melting point has been determined to be 5.94±0.06 g/cm3. The use of the floating crucible technique for the growing of uniform silicon crystals is discussed.

ISSN:0021-8979    

DOI:10.1063/1.1723411

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

A ferromagnetic material having a rectangular hysteresis loop can be magnetized much easier if a magnetic field is applied transverse to the direction of remanence at the same time the remagnetizing pulse is applied. This effect, which has been observed in cores of ferrite, rolled Permalloy and vacuum‐deposited alloys, is shown to be compatible with the existing theories of domain wall motion. It forms the basis of an improved method of writing into magnetic memory cores in a digital computer.

ISSN:0021-8979    

DOI:10.1063/1.1723412

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

A previously developed nondestructive piezoelectric method for studying the state of polarization of ferroelectric crystals is applied to study polarization switching in barium titanate single crystals.We propose three polarization processes. The first and second processes were designated nucleation and growth by Merz. The third process cannot be measured by conventional pulse methods, and has a very slow polarizing velocity. This indicates the existence of layers which lie between the surface layer and inner layer.Switching time results are considered in the light of the above experiments.

ISSN:0021-8979    

DOI:10.1063/1.1723413

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The damage produced in neutron irradiated boron glass by the products of the (n,&agr;) reaction appears as a pronounced optical birefringence. This birefringence is shown to be due to macroscopic stresses resulting from volume contraction of the glass. The variation of strain with depth from the glass surface is found to fit to a remarkable degree the space rate of decay of radiation of suitable velocity distribution and random direction. This permits the determination of the neutron velocity by one‐velocity theory, or of the most probable velocity for a Maxwellian neutron distribution; in addition the average volume contraction corresponding to a single neutron‐boron reaction is found to be equal to 3.6×10−19cm3per (n,&agr;) reaction.

ISSN:0021-8979    

DOI:10.1063/1.1723414

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1723416

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1723418

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1723419

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1723420

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1723421

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1723423

出版商:AIP    

年代:1958

数据来源: AIP