Spin Dependent Transport in Nanomagnets One of the main challenges in nanomagnetism research is the detection of spin state at nanoscale. It is extremely difficult to measure the magnetization of single nanomagnets because the output signal is beyond the detection limit of most conventional magnetometers. Magnetoresistance measurements have been widely used to investigate the reversal mechanism and map the magnetization states in individual nanostructures (nanoelements). This technique, however, is normally implemented by fabricating the contact probes directly on the nanostructures. Consequently, the magnetoresistance response is strongly dependent on the contact configuration. This approach may result in a detrimental shunting effect. Any probing technique that maps the spin states of the entire ring structure without any dependence on the electrical contact configuration is desirable. Recently, we developed a novel synchronous transport measurement technique for probing the magnetic configurations in ferromagnetic rings electrically without placing the electrical contact leads directly on the nanostructures. This was achieved by fabricating the contact pads on magnetic nanowires attached to the nanostructures. This involves the use of strong dependence of the coercive field on the lateral size to create a new magnetic system whose spin dependent transport properties uniquely depend on the combination of spin orientations of each part of the device. We have:
Further readings:
|