Current-perpendicular (CPP) magnetoresistance in magnetic metallic multilayers

We present an experimentalist's view of the theory and published data for the magnetoresistance (MR) of a multilayer composed of alternating ferromagnetic (F) and non-magnetic (N) metals measured with current flow perpendicular to the layer planes (CPP-MR). We explain the advantages of this geometry for determining the fundamental quantities underlying spin-polarized transport, describe the different techniques developed to measure the CPP-MR, summarize the salient features of the models used to analyze experimental data, and describe tests of those models. We then review what has been learned so far about spin-dependent scattering anisotropy and spin relaxation in F-metals and at F/N interfaces, specific resistances of F/N interfaces, the temperature dependence of spin-polarized transport parameters, and mixing of the spin-polarized electron currents. After a brief overview of some new directions, we conclude with a list of questions still to be answered.     

Gauge symmetry and the EMC spin effect

We emphasise the EMC spin effect as a problem of symmetry and discuss the renormalisation of theC=+1 axial tensor operators. This involves the generalisation of the Adler-Bell-Jackiw anomaly to each of these operators. We find that the contribution of the axial anomaly to the spin dependent structure functiong ₁(x, Q ²) scales at O(α_s). This means that the anomaly can be a largex effect ing ₁. Finally we discuss the jet signature of the anomaly.     

Cr,Nd:YAG self-Q-switched laser with high efficiency output

The high efficient laser performance of self-Q-switched laser in the co-doped Cr⁴⁺,Nd³⁺:YAG microchip with 1.8 mm thickness was demonstrated. The slope efficiency is varied with the reflectivity of output coupler at 1064 nm, and the highest slope efficiency of 26% was obtained for 95% reflectivity of output coupler at 1064 nm. The pulse width, the single pulse energy and the pulse repetition rate for different reflectivity of the output couplers were measured, and the experimental results agree with the numerical calculations of the passively Q-switched rate equations. This can lead to develop the diode laser pumped monolithic self-Q-switched solid-state microchip lasers, especially for the intracavity frequency-doubled solid-state microchip lasers.     

Cr∶Nd∶GSGG晶体1.061 μm受激发射截面随温度变化特性研究

测量了Cr∶Nd∶GSGG晶体从 - 70℃到 +80℃温度下的荧光发射光谱和荧光寿命 ,计算了该晶体在不同温度下 1 .0 61 μm受激发射截面 ,获得在此温度变化范围内受激发射截面随温度的线性变化关系     

Partons and the EMC spin effect

We focus on the parton model and the role of the axial anomaly in polarised deep inelastic scattering. We show that the axial anomaly is relevant to each of the higher moments of the spin dependent structure functiong ₁ (x) and not just the first moment. This result implies that the factorisation of mass singularities is not sufficient to define the parton model in spin dependent QCD. (It is certainly a necessary condition.) We also need to consider the locality of the photon parton interaction. The anomaly is observed over allx in the EMCg ₁ (x) data.     

Effect of the surface roughness on Bean-Livingston surface barrier

Bean-Livingston barrier for a single Abrikosov vortex interacting with the rough surface is calculated as a function of the random characteristics of the surface roughness. It has been shown that even a respectively smooth surface roughness results in an essential decrease of the Bean-Livingston surface barrier.     

Inclusive ηp and ηn charged-current neutrino reactions below 6 GeV

Results are presented of a study of inclusive ηp and ηn interactions from threshold to 6 GeV. The data show a rapid approach to the distributions expected in the naive quark-parton model. The charged-current η deuteron total cross section is fit by the expression σ_T(ηd) = (0.76 ± 0.03) × 10^?38E_η cm² per GeV per nucleon. For E_η > 1.5 GeV, we measure σ_T(ηn)/σ_T(ηp) = (2.02 ± 0.23). The distributions in the scaling variables x and y are given and discussed.     

Die Knickung verwundener Stäbe als technisches Beispiel zur Schaeferschen Theorie zweiparametriger Eigenwertprobleme

Übersicht In der vorliegenden Arbeit wird die Schaefersche Theorie zweiparametriger Eigenwertaufgaben auf die Knickung verwundener Stäbe angewendet. Es wird gezeigt, daß die Schaefersche Theorie die schnelle Abschätzung der kritischen Lasten für die verwundenen Knickstäbe ermöglicht und daß der dabei begangene Fehler für alle technischen Zwecke zu vernachlässigen ist.

---

Summary This paper deals with an application of Schaefer's theory of two-parametric eigenvalue problems to the stability of twisted columns. It is shown that Schaefer's theory allows a quick estimate of the critical loads of the twisted columns and that the error involved in such an estimate may be neglected for all technical purposes.

---

---

Herrn Prof. Dr.-Ing. Hermann Schaefer zum 60. Geburtstag gewidmet. Die Verfasser danken der Deutschen Forschungsgemeinschaft für die Unterstützung dieser Arbeit.