A previous work doing in The Hong Kong University (HKU) and The Hong Kong University of Science and Technology (HKUST) showing an electric current is observable upon optically injected spin current at 77K, while a specially designed crossbar structure enables this to happen....[ Read more ]

A previous work doing in The Hong Kong University (HKU) and The Hong Kong University of Science and Technology (HKUST) showing an electric current is observable upon optically injected spin current at 77K, while a specially designed crossbar structure enables this to happen.

In this thesis, the experiment was repeated at room temperature and external magnetic field was applied. There were signals detected as the quarter waveplate was set at 45°. Detectable signals at room temperature shows the crossbar structure could be used in spin detection for a spin field effect transistor (spin FET). The impact of external magnetic field perpendicular to the sample showed that the spin current photo-generated were out of plane. It was demonstrated that the external magnetic field could not be influential to the polarization dependence.

Spin current injection was achieved by illumination of LPL. Spin current manipulation was done by rotating the polarization of LPL. Spin current detection was done by measuring electrical potential difference across electrodes, while spin current was converted into electrical current by the scattering of edges around crossing region.