Gyrotropic propagation of vertical Bloch lines

Vertical Block line (BL) gyrotropic propagation was studied experimentally. Single BLs nucleated in an as-grown (YSmBi)/sub 3/(FeGa)/sub 5/O/sub 12/ garnet film were viewed directly using the PADO (polarized anisotropic dark-field observation) technique. Gyrotropic force was provided by an asymmetrical triangular-shaped bias field pulse. A short-risetime pulse moved the line of a straight wall in one direction, whereas a large-risetime pulse moved it backward. This gyrotropic propagation phenomenon is reproducible for varying bias field; however, some scatter is observed in BL displacement. Block wall response to the bias field pulses is also considered. The range of effective drive field inducing good gyrotropic propagation is discussed.<
>