Controlling of sub-μm² domains in spin valve strips with conductor current

Nucleation and erasing of sub-μm² domains in spin valve strips have been performed with current pulses applied through conductors. A spin valve material of NiFe/Co/Cu/Co was deposited by magnetron sputtering and patterned into sense lines of 40 parallel strips with 0.4 μm width and 2 μm pitch. Selective domain nucleation under parallel conductors with l μm width and 2.6 μm pitch has been confirmed by the current induced MR change. Pulses with opposite polarity performed erasing of nucleated domains. Reproducible MR change with a variation of ±10 % relative to the mid value was realized in 10⁴ operations of the domain nucleation process.