A new nondestructive readout system for domain-wall motion of magnetic film

A new highly sensitive and reliable NDRO system based on the planar Hall effect has been developed for the purpose of signal detection in the thin film domain-wall motion devices. In this system, the output channel of these devices is placed perpendicular to the magnetic easy axis of the planar Hall element (PHE). The measured maximum sensitivity of signal detection in this system is of the order of 50 mV/A. For the PHE tested, the maximum useful continuous current is 20 mA, and the frequency response is flat at least up to 10 MHz. Upon switching the domain tip at the output channel, a reliable output voltage of 1 mV is obtained for the continuous PHE current of 20 mA in this system. This readout system has been used for signal detection in the domain tip shift register. The output voltage waveforms are shown.