Abstract: A device for sensing a magnetic field is described. The device comprises first, second and third leads and a junction between the leads. The junction and leads are arranged in a plane and the junction is configured to exhibit quantum confinement in a direction perpendicular to the plane. The first lead is arranged on one side of the junction and the second and third leads are arranged on an opposite side of the junction. The first lead is configured to limit angle of spread of charge carriers entering the junction so that, when charge carriers flow into the junction from the first lead, the charge carriers form a substantially nondivergent beam.

Abstract: Methods of lapping rows of recording heads are described after an air bearing surface (ABS) damascene process is performed. The ABS damascene process uses a selective etching process to form voids in the row of recording heads where conductive material forms a feature in the recording head, such as a wrap around shield. The conductive material is then deposited on the ABS of the row to fill the voids, and the row is lapped. According to methods provided herein, the resistance of one or more lapping guides in the row of recording heads is monitored to determine when the conductive material is removed by the lapping process. When the monitored resistance indicates that the conductive material is removed, the lapping process is stopped. The resistance across one or more lapping guides may also be used to control the lapping process to uniformly lap the conductive material from the ABS.

Abstract: A device for sensing a magnetic field is described. The device comprises first, second and third leads and a junction between the leads. The junction and leads are arranged in a plane and the junction is configured to exhibit quantum confinement in a direction perpendicular to the plane. The first lead is arranged on one side of the junction and the second and third leads are arranged on an opposite side of the junction. The first lead is configured to limit angle of spread of charge carriers entering the junction so that, when charge carriers flow into the junction from the first lead, the charge carriers form a substantially nondivergent beam.

Abstract: Methods of lapping rows of recording heads are described after an air bearing surface (ABS) damascene process is performed. The ABS damascene process uses a selective etching process to form voids in the row of recording heads where conductive material forms a feature in the recording head, such as a wrap around shield. The conductive material is then deposited on the ABS of the row to fill the voids, and the row is lapped. According to methods provided herein, the resistance of one or more lapping guides in the row of recording heads is monitored to determine when the conductive material is removed by the lapping process. When the monitored resistance indicates that the conductive material is removed, the lapping process is stopped. The resistance across one or more lapping guides may also be used to control the lapping process to uniformly lap the conductive material from the ABS.