| 摘要 |
PURPOSE:To measure a polarization ratio almost without being affected by a change of the surface condition of an electron beam-radiated object by changing the radiation direction to the object with the polarization direction kept constant. CONSTITUTION:An electron beam 1 to be measured is fed between two pairs of deflection electrodes 3, 3' arranged at a right angle to each other applied with sinusoidal wave voltage Vr, Vr' out of phase by 90 deg. from a generator 7 through a collimator 2, and it is rotated around a center axis 9 as shown by an arrow R while the angle alpha between the center axis 9 and the electron beam 1 is kept constant. Furthermore, the electron beam 1 is fed through the axial symmetry DC electric field Er generated by ringlike deflection electrode systems 4, 4' while the angle alpha with the center axis 9 on a metal polycrystal target 6 with a surface vertical to the center axis 9 is kept constant and the incidence direction is rotated. The absorbed current is synchronously detected by a signal processor 8 with a signal from the generator, the polarization direction is calculated, and the spin polarization ratio is calculated based on the ratio between the secondary electron current from the target collected by a collector 5 and the sum of the absorbed current. |
