摘要:

It is shown that in a thin‐film optical slab‐type directional coupler, the synchronization condition can be controlled by adjusting the thickness of an additional high‐index top layer. Damped oscillation was accompanied by the absorbing property of the top‐layer material.

ISSN:0021-8979    

DOI:10.1063/1.328059

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Conditions sufficient for the electrolytic exchange of D+for H+ions in synthetic quartz are established. The deuterium‐swept quartz crystals are characterized by electron paramagnetic resonance and infrared absorption.

ISSN:0021-8979    

DOI:10.1063/1.328025

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Lead filamentary crystals have been subjected to finite deformations. The parameter &dgr; associated with deviations from linearity in Hooke’s law in the form &egr;=s′11&sgr; +&dgr;(s′11&sgr;)2(where &egr; is the strain, &sgr; the stress, ands′11Young’s modulus along the whisker axis) has a value of 4.2±0.6 for four crystals oriented in the ⟨110⟩ direction. The resulting linear combination of third‐order constants is,C111−4.6C112+3.6C123+3.1C144−3.7C166=4.4×1011N/m2.

ISSN:0021-8979    

DOI:10.1063/1.328026

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

We examine the field pattern produced by the four‐electrode system attached symmetrically to both sides of a film which was investigated by Hirota. We provide a conformal transformation which ensures that an electric field line is coincident with the film surface. The conductivity in the film is calculated and compared with experimental results.

ISSN:0021-8979    

DOI:10.1063/1.328027

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

In reply to Wintle and Chapman, we point out that in the experimental condition, the allowed geometry factor of four‐electrode system will be limited within a range of values.

ISSN:0021-8979    

DOI:10.1063/1.328028

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

From theoretical and experimental investigations on 1/fnoise in the Hall voltage at high magnetic induction it is concluded that 1/fnoise is caused by mobility fluctuations.

ISSN:0021-8979    

DOI:10.1063/1.328029

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

A general critical state model describes the field and current distributions in a hard Type II superconductor with a local relation between the field and current density. We show here that such models cannot provide a magnetically shielded region in superconducting wires in zero applied field.

ISSN:0021-8979    

DOI:10.1063/1.328030

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Previous measurements of secondary electron emission from vanadate‐phosphate glasses, using extremely clean surfaces, suggest that where these materials are used in practice as secondary emitters, surface contamination by materials such as cesium plays an important role. Samples of glasses containing significant quantities of cesium in the initial melt were manufactured, and did indeed show increases of 50% or more in the secondary electron emission yield. The yield increased monotonically with cesium content for all samples tested. The inelastic reflection coefficient for these materials was high—about 0.2. Similar materials containing sodium rather than cesium behaved very similarly where the V2O5content was 60% or more, although the reflection coefficient was lower—about 0.1. Where the V2O5content was less than 60%, however, high sodium concentrations produced a drastic fall in yield. V2O5‐P2O5‐Cs2O or V2O5‐P2O5‐Na2O glasses are easily manufactured by the same techniques as V2O5‐P2O5materials, and in view of their increased secondary electron emission coefficient, they should prove useful as secondary emitters in a variety of applications.

ISSN:0021-8979    

DOI:10.1063/1.328031

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

A new technique based on deposition of metallic film at room temperature followed by laser irradiation, for the formation of Ohmic Contacts on semiconducting oxides, has been developed. Aluminum or nickel film about 1 &mgr;m thick was deposited onn‐type polycrystalline barium titanate (BaTi03) substrates and irradiated withQ‐switched ruby laser pulses. This technique produces low‐resistance Ohmic contacts which do not age and remain stable over a wide temperature range.

ISSN:0021-8979    

DOI:10.1063/1.328032

出版商:AIP    

年代:1980

数据来源: AIP