Flux-enhanced giant magnetoresistive head design and simulation

Analyses of field distributions and undershoots in GMR-type differential readers

“…2(c) shows the close-up of the B y profiles around the transition, with and without the FLs. The field distribution is relatively uniform (non-uniform) in the absence (appearance) of free layers; for the latter case, the overall large field within the FL is due to a large permeability [8] used and the very large field at the left corner of the left FL is due to field singularity. The field-singularity behavior can be visualized by the flux line distributions in Fig.…”

Evaluation of read channel performance for perpendicular patterned media

“…In the following analysis, a GMR head with a sensor thickness (along track) of 4 nm and a shieldto-shield separation of 90 nm has been used [5]. The model predicts the isolated pulse response due to varying media characteristics such as island length, film thickness, GMR head fly height and the presence or not of a soft magnetic underlayer (SUL) of infinite permeability.…”

Ultra-Compact 100 × 100 μm2 Footprint Hybrid Device with Spin-Valve Nanosensors

“…While the spatial resolution is mostly dependent on the size of the structures, the field sensitivity of SV sensors can be improved by incorporating these structures in the gap of magnetic flux concentrators (MFC) [ 6 , 7 , 8 ]. This strategy has been widely used for magnetic sensors [ 9 , 10 , 11 ], and has pushed the field detection level of SVs down to sub-nanoTesla range at room temperature [ 12 , 13 ].…”

“…Silva et al showed systematically that smaller air gaps minimize magnetic flux leakage and provide a more effective concentration of the magnetic field upon the sensor with direct consequence of increased sensor sensitivity [ 8 ]. However, and since MFCs are usually composed of hundreds of nanometers thick films [ 7 ], defining poles with gaps from few μm down to sub-μm sizes is an important microfabrication challenge, which may lead to major improvements in field concentration gain factors.…”