A read head includes a first ferromagnetic layer, a second ferromagnetic layer, a first diffusion-assist nonmagnetic metallic layer located between the first ferromagnetic layer and the second ferromagnetic layer, a second diffusion-assist nonmagnetic metallic layer located between the first ferromagnetic layer and the second ferromagnetic layer, and a semiconductor spacer layer located between the first diffusion-assist nonmagnetic metallic layer and the second diffusion-assist nonmagnetic metallic layer.

In one general embodiment, an apparatus includes a magnetic sensor structure, a magnetic shield having at least one laminate pair comprising a magnetic layer and an electrically conductive nonmagnetic layer, and a nonmagnetic spacer layer between the sensor structure and the magnetic shield. In another general embodiment, an apparatus includes a magnetic tunnel junction sensor structure, and a magnetic shield having at least two laminate pairs, each pair comprising a magnetic layer and an electrically conductive nonmagnetic layer. A deposition thickness of the nonmagnetic layer in each laminate pair is about 10% or less of a total deposition thickness of the laminate pair.

A magnetic read head is provided, comprising a bottom magnetic shield, a first free magnetic layer, a second free magnetic layer, and a top magnetic shield, arranged from bottom to top in this order in a stacking direction from a leading side to a trailing side of the read head. A non-soft bias layer is positioned below the top magnetic shield and on a back side of the first and the second free magnetic layers. The top magnetic shield has a unidirectional anisotropy, the magnetic moments of the top and the bottom magnetic shields are canted relative to a plane of the first and the second free magnetic layers, and the top and the bottom magnetic shields are decoupled from the non-soft bias layer and not magnetically coupled to a soft bias layer.

The present disclosure generally relates to a dual free layer (DFL) read head. In one embodiment, a dual free layer (DFL) read head, comprising: a tunnel magneto resistance (TMR) sensor disposed at a media facing surface (MFS); soft bias (SB) side shields disposed adjacent to the TMR sensor at the MFS; and a rear soft bias (RSB) disposed adjacent to the TMR sensor recessed from the MFS. The RSB has a nonmagnetic cap, the nonmagnetic cap comprising: a first nonmagnetic cap layer; and a second nonmagnetic cap layer, wherein an etch selectivity of the first nonmagnetic cap layer to the second nonmagnetic cap layer is a ratio of a:b in a first chemistry and a ratio of x:y in a second chemistry, wherein a is greater than b, and y is greater than x, and the second nonmagnetic cap layer is disposed on the first nonmagnetic cap layer.

According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium, a magnetic head, and a processor. The magnetic head includes a first reproducing element portion and a second reproducing element portion. The processor is configured to acquire a first signal and a second signal, and to output an output signal according to either one of the first signal and the second signal. The first signal is obtained by reproducing information recorded on a first recording region by the first reproducing element portion. The second signal is obtained by reproducing the information recorded on the first recording region by the second reproducing element portion.

A magnetic read head is provided, comprising a bottom magnetic shield, a first free magnetic layer, a second free magnetic layer, and a top magnetic shield, arranged from bottom to top in this order in a stacking direction from a leading side to a trailing side of the read head. A soft bias layer is positioned below the top magnetic shield and on a back side of the first free magnetic layer and second free magnetic layer. The soft bias layer is directly coupled to the top magnetic shield, and the top magnetic shield has a unidirectional anisotropy, thereby reducing the incidence of soft bias magnetization reversal and avoiding hysteresis in the transfer curve.

A magnetic read head is provided, comprising a bottom magnetic shield, a first free magnetic layer, a second free magnetic layer, and a top magnetic shield, arranged from bottom to top in this order in a stacking direction from a leading side to a trailing side of the read head. A soft bias layer is positioned below the top magnetic shield and on a back side of the first free magnetic layer and second free magnetic layer. The soft bias layer is directly coupled to the top magnetic shield, and the top magnetic shield has a unidirectional anisotropy, thereby reducing the incidence of soft bias magnetization reversal and avoiding hysteresis in the transfer curve.

A multi-sensor reader that includes a first sensor that has a sensing layer with a magnetization that changes according to an external magnetic field. The first sensor also includes first and second side biasing magnets having a magnetization substantially along a first direction. The first and second side biasing magnets align the magnetization of the sensing layer substantially along the first direction when the sensing layer is not substantially influenced by the external magnetic field. The multi-sensor reader further includes a second sensor that is stacked over the first sensor. The second sensor includes a reference layer that has a magnetization that is set substantially along a second direction. The first sensor further includes at least one sensor-stabilization feature that counteracts an influence of a magnetic field utilized to set the magnetization of the reference layer of the second sensor in the second direction on the magnetization of at least one of the first and second side biasing magnets in the first direction.

A scissor type magnetic sensor for magnetic data recording having a flux closure magnetic side shield structure. The magnetic sensor has a magnetic side shield structure that includes a non-magnetic layer within a magnetic material layer, with the non-magnetic layer being removed from the sensor stack so as to define upper and lower magnetic portions of the magnetic structure that are separated from one another at a region away from the sensor stack. The upper and lower magnetic portions are connected with one another in a region near the sensor stack so as to magnetic flux closure structure. The novel magnetic side shield structure provides net neutral magnetization that does not provide an inadvertent biasing to the magnetic free layers of the magnetic sensor.

A scissor type magnetic sensor for magnetic data recording having a flux closure magnetic side shield structure. The magnetic sensor has a magnetic side shield structure that includes a non-magnetic layer within a magnetic material layer, with the non-magnetic layer being removed from the sensor stack so as to define upper and lower magnetic portions of the magnetic structure that are separated from one another at a region away from the sensor stack. The upper and lower magnetic portions are connected with one another in a region near the sensor stack so as to magnetic flux closure structure. The novel magnetic side shield structure provides net neutral magnetization that does not provide an inadvertent biasing to the magnetic free layers of the magnetic sensor.