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In this work, photostrictive manipulations of static and dynamic magnetic properties are demonstrated in an extrinsic multiferroic composite. The photostriction is achieved with visible light in the blue region of the spectrum. The composites consist of 5 nm or 10 nm magnetostrictive Fe$_{81}$Ga$_{19}$ thin films coupled to a piezoelectric (011)-Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_3$-Pb(Zr,Ti)O$_3$ substrate. Angular dependent magnetization reversals properties are largely enhanced or reduced under a converse magneto-photostrictive effect (CMPE). The CMPE strength is analysed with a novel coefficient named the converse magneto-photostrictive coupling coefficient. This coefficient is proposed as a general approach to analyse and to compare different extrinsic multiferroics under the converse magneto-photostrictive effect. Its thickness dependence reveals that the CMPE strength decreases with an increase of the Fe$_{81}$Ga$_{19}$ thickness. Experimental evidence for a control of dynamic magnetic properties under CMPE is then revealed by ferromagnetic resonance measurements. Resonant fields are shifted under CMPE, whereas their linewidths remain constant. Furthermore, resonant field shifts can be either positive or negative depending on the in-plane angle. The largest shift under CMPE of +5.7 % is obtained for the 5 nm sample. Our study shows that the CMPE provides an efficient approach for a control of not only the static but also the dynamic magnetic properties in extrinsic multiferroics., Comment: Submitted to Nature Materials

Magnetoelectric composites are an important class of multiferroic materials that pave the way towards a new generation of multifunctional devices directly integrable in data storage technology and spintronics. This study focuses on strain-mediated electrical manipulation of magnetization in an extrinsic multiferroic. The composite includes 5 nm or 60 nm Fe$_{81}$Ga$_{19}$ thin films coupled to a piezoelectric (011)-PMN-PZT. The magnetization reversal study reveals a converse magnetoelectric coefficient $\alpha_\mathrm{CME,max} \approx 2.7 \times {10^{-6}}$ s.m$^{-1}$ at room temperature. This reported value of $\alpha_\mathrm{CME}$ is among the highest so far compared to previous reports of single-phase multiferroics as well as composites. An angular dependency of $\alpha_\mathrm{CME}$ is also shown for the first time, arising from the intrinsic magnetic anisotropy of FeGa. The highly efficient magnetoelectric composite FeGa/PMN-PZT demonstrates drastic modifications of the in-plane magnetic anisotropy, with an almost 90$^{\circ}$ rotation of the preferential anisotropy axis in the thinner films under an electric field E = 10.8 kV.cm$^{-1}$. Also, the influence of thermal strain on the bilayer's magnetic coercivity is compared to that of a reference bilayer FeGa/Glass at cryogenic temperatures. A different evolution is observed as a function of temperature, revealing a substrate thermo-mechanical influence which has not yet been reported in FeGa thin films coupled to a piezoelectric material.

This report, one of nine provincial reports from South Africa, focuses on the 1996's School Register of Needs Survey, one of the foundations of the new government's commitment to equity in education provision and improving the quality of learning and teaching. The School Register of Needs Survey's objectives were to locate and map every educational institution in the country; survey the physical facilities, conditions of buildings, and services provided; and establish a database of all school information collected. The North West Province 2413 schools were surveyed; of these, 67.18% were primary-school-level institutions, 26.14%, secondary-level schools, 5.01%, combined schools, 0.04%, technical colleges, and 1.62% were special schools. Chapters include: (1) "School Register of Needs Survey"; (2) "Third International Mathematics and Science Study (TIMSS); (3) "Longitudinal Survey of Scholastic Achievement"; (4) "Overage Learners"; (5) "Matriculation Results (1996)"; (6) "Register of Graduates"; and (7) "Summary." An appendix presents school register of needs survey data per magisterial district for the North West Province. Twelve maps are also appended. Contains 29 figures and 9 tables. (BT)