Schematics of thin film modification beginning with the sputter deposited full film layer stack (a), followed by photolithography and Ar-ion etching (b), and a postannealing step at , (c). The modulated magnetic and structural properties are sketched in (d).
Cross-sectional TEM micrograph of a film structure after etching and annealing at , . The stripe interface shows a step width of about 20 nm.
Magnetic properties of (a) a quasifree NiFe/IrMnO and (b) an exchange biased NiFe/IrMn film structure measured parallel and perpendicular to on extended reference films. The positions of and are indicated.
Magnetization loops for laterally magnetostructured NiFe (30 nm)/IrMn/Ta stripes of width, aligned parallel (a) and perpendicular (b) to , measured along and perpendicular to in each case. (c)–(f) Change of coercivity field strengths and exchange bias fields with stripe period calculated from and , respectively, and , [as indicated in (a) and (b)] for all investigated stripe widths. The orientation of the stripes relative to is indicated. In the left column (c),(e) the data for the parallel aligned stripes and in the right column (d),(f) for perpendicular arranged stripes are given. The range of and of the full film data (Fig. 3) is indicated by horizontal lines.
Quantitative domain image of stripes aligned parallel to the modulated . (a) and (b) show the conventional domain images acquired at longitudinal and transversal Kerr sensitivity at an external field close to . (c) shows the quantitatively determined magnetization distribution of the Kerr images (a) and (b) with the magnetization vectors overlayed as black arrows. The exchange biased stripes are indicated by dark (red) bars next to the Kerr images.
Magnetic hysteresis and domain images for the 20 and broad stripes aligned parallel of the . The hysteresis loops along the easy directions are given in longitudinal and transverse sensitivity (b),(e). Domain states occurring along the magnetization loops along the forward (a),(d) and recoil branch (c),(f) are acquired with the magneto-optical sensitivity axis aligned for longitudinal contrast. The dark (red) bars mark the exchange biased stripes. The field values are indicated as full (a),(d) and open (c),(f) symbols in both hysteresis loops and in the Kerr images. The net magnetization of the resulting quasidomains is sketched by open (yellow) arrows.
Schematic magnetization configuration for the closure domain patterns of (a) free and (b) exchange biased stripes along the forward hysteresis branch of the . The exemplary Kerr images are recorded in longitudinal contrast and are the same as in Fig. 6(a), and .
Domain states and magnetic hysteresis of the 20 and stripes aligned perpendicular to . The field values of the given states [(a),(d) and (c),(f)] along the easy direction are indicated as symbols in the according magnetization loop (b),(e). The magneto-optical sensitivity axis was aligned for longitudinal contrast .
Ratio of NiFe/IrMn:NiFe/IrMnO for all stripe widths calculated from the stripe widths measured by AFM.
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