To obtain the spatial feature of arterial pulse, a spatial pulse diagnostic apparatus was designed using a two-dimensional magnetoresistive sensor array. The magnetic-field distribution for the magnet array was simulated using the finite-element method. The field distribution of parallel magnet arrays was observed to be more sensitive and uniform than that of the perpendicular ones. Moreover, the spatial displacements of the magnet array coincided with the output signal of the magnetic tunneling junction sensor array.

The dependences of the stack number and Co and Cu thicknesses on magnetoresistance, and perpendicular exchange biasing in the [Pd∕Co]×N1∕Cu∕Co∕[Pd∕Co]×N2∕FeMn spin valves, were investigated. The magnetoresistance ratio of the spin valves with N1=4 and N2=2 was above 5% for the Cu between 1.5 and 2.5nm, and the exchange-biasing field (Hex) was increased to 600Oe. When the Co thickness over the Cu layer was increased from 0.48to1.28nm, the ratio likewise rose to 7.4% due to the strengthened spin-dependent scattering effect. Moreover, the Co thickness below the Cu layer rose to 9.1%. The maximum ratio of 10.2% was obtained in the structure of the [Pd0.8∕Co0.32]×2∕Pd0.8∕CoFe0.48∕Cu2.25∕CoFe0.6∕[Pd0.8∕Co0.48]×2∕FeMn15 (nanometer) multilayer with Hex=450Oe.

The magnetic domain walls at the edges of a large patterned and exchange‐biased NiO (10–60 nm)/NiFe (10 nm) bilayers and their motions with applied field were investigated by MFM. Three kinds of domain walls were found at the edges of the NiO (30 nm)/NiFe (10 nm) bilayer having the exchange biasing field (Hex) of 21 Oe. Two zigzag charged walls and Néel wall appeared at the edges perpendicular and parallel to Hex, respectively. The zigzag charged walls are nearly a factor of three wider than the Néel wall, and were not observed for the strong exchange‐biased bilayer (60 nm NiO, H ex = 75 Oe). We investigated the subsequent motion of the walls, and identified the pinning and nucleation sites during magnetization reversal. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)