Abstract—a new versatile scanning hardware based on a Micromagnetics® STJ-020 MgO-based tunnelling magneto-resistance (TMR) sensor has been developed to volumetrically scan the thin boundary layer above a given sample. An (x,y) planar scan of the surface of a 7.5 mm × 7.5 mm sample of grain-oriented (3% Si) electrical steel is presented. Stray fields normal to the surface between -116 and 272 A/m are measured. At 10 μm/pixel domain and micro-domain structures are seen. At 5 μm/pixel the micro-domain structures resolve into clear Lancet domains. The domain images presented have greater qualitative similarity with Kerr effect observations than with Bitter technique results. An (x,z) vertical scan along a 2.35 mm transect reveals the perpendicular extent of the stray fields, with the normal components shown to emanate from the domain bodies and extend approximately 40 - 100 μm from the sample surface. With the aim of investigating how the stray fields close back onto the surface, the (x,z) transect is repeated with the sensor at 5, 10, 15 and 20 degrees from the vertical. For the first time, the stray fields from surface domains viewed by other techniques in only a planar (x,y) projection have been s
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机译:摘要—基于Micromagnetics®STJ-020基于MgO的隧道磁阻(TMR)传感器的新型多功能扫描硬件已经开发出来,可以对给定样品上方的薄边界层进行体积扫描。提出了一个7.5 mm×7.5 mm晶粒取向(3%Si)电工钢样品表面的(x,y)平面扫描。测量垂直于表面的杂散场,介于-116和272 A / m之间。在10μm/像素处,可以看到微区结构。在5μm/像素下,微域结构解析为清晰的柳叶刀域。呈现的域图像与Kerr效应观察结果相比,与Bitter技术结果具有更大的定性相似性。沿2.35 mm横断面的(x,z)垂直扫描显示了杂散场的垂直范围,正常成分显示为从畴体发出,并从样品表面延伸约40-100μm。为了研究杂散场如何闭合回到表面上,用与垂直方向成5、10、15和20度的传感器重复(x,z)横断面。第一次,其他技术仅在平面(x,y)投影中观察到的来自表面域的杂散场为s
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