Domain Orientation in Single Crystal TbFe(2) and Tb(.27)Dy(.73)Fe(2),
Abstract:
The investigators have observed 71 and 109 degree walls in single crystal TbFe2 and Tb.27Dy.73Fe2 Terfenol via the Kerr effect and synchrotron radiation topographs. A Terfenol 110 surface exposed to synchrotron radiation showed stripe-like domains with 110, 109 degree walls and 001, 71 degree walls. Cooling to approx. 273K caused an easy axis switch from 111 to 100 no domains were visible. Warming back to approx. 293K brought out mostly 109 degree walls. Stripelike domains were also seen in 110 and 100 TbFe2 surfaces via the Kerr effect. In the 110 sample H fields along 001 and 110 directions created 109 and 71 degree walls respectively. With H applied at approx. 45 degree to both 001 and 110 directions 71 and 109 degree walls appeared simultaneously. The domain widths varied from 5 to 250 micrometers and fields of approx. 3000 Oe away from 001 and 110 directions saturated the sample. Walls in the 100 sample were also 71 or 109 degree but were only 2 to 15 micrometers wide.