Embodiments of the present disclosure generally relate to a write head for a magnetic recording device. The write head includes a spin torque oscillator (STO) that has a seed layer formed on a write pole, a spin polarization layer (SPL) formed on the seed layer, a first spacer layer formed on the SPL, a field generation layer (FGL) formed on the first spacer layer, a second spacer layer formed on the FGL, and a notch formed on the second spacer layer. The FGL and the notch are antiferromagnetically coupled through the second spacer layer and thus increases the FGL angle and improves the write capabilities of the write head.

A hard disk drive includes composite magnet as voice coil motor magnet, where a composite permanent magnet comprising: a first magnet (M1), a second magnet (M2) and a third magnet (M3). M1, M2 and M3 are deposited, bonded, sintered, glued or assembled together and next to each other. The directions of the saturation magnetization of M1 and M3 are opposite to each other. The direction of the saturation magnetization of M2 is substantially perpendicular to the direction of saturation magnetization of M1 and M3.

A hard disk drive includes a drive case and a cover plate, the storage media platers and a spindle, the recording heads and actuators, the connection port, the control logic board and one or more voice coil motor, where the actuators are operated via a voice coil motor; wherein the voice coil motor magnets comprise of a pair of composite permanent magnets on both sides of the voice coil, where each piece of composite permanent magnet comprising: a first core magnet M1, a cladding magnet Mc12 and a second core magnet M2; the magnetization direction of M1 and M2 are opposite to each other; the magnetization direction of Mc12 is substantially perpendicular to the magnetization direction of M1 and M2; the ratio of the width of Mc12 to the thickness or the height of Mc12 is 4:1 or less as seen from the back view.

A hard disk drive includes a drive case and a cover plate, the storage media platers and a spindle, the recording heads and actuators, the connection port, the control logic board and one or more voice coil motor, where the actuators are operated via a voice coil motor; wherein the voice coil motor magnets comprise of a pair of composite permanent magnets on both sides of the voice coil, where each piece of composite permanent magnet comprising: a first core magnet M1, a cladding magnet Mc12 and a second core magnet M2; the magnetization direction of M1 and M2 are opposite to each other; the magnetization direction of Mc12 is substantially perpendicular to the magnetization direction of M1 and M2; the ratio of the width of Mc12 to the thickness or the height of Mc12 is 4:1 or less as seen from the back view.

This invention presents a new integrated composite permanent magnet (CPM) structure with precise control over component dimensions and magnetic properties, along with an efficient and cost-effective method for achieving this configuration. The composite magnet provides a stronger magnetic field than traditional magnets, making it suitable for motor and generator applications that require high performance. Specifically, for voice coil motors (VCMs), the composite magnet structure enhances VCM efficiency while consuming the same or fewer rare earth materials. One embodiment of the composite magnet includes a cladding magnet between two core magnets, with opposing magnetization directions, while the cladding magnet's magnetization is perpendicular to the core magnet's magnetization. The difference in thickness between the core and cladding magnets is within 5 micrometers or less, or <1% of the magnet's thickness. The invention also discloses novel manufacturing processes for achieving highly efficient composite magnets with high accuracy control of magnet dimensions. One embodiment involves a reorientation and stacking process added to the conventional NdFeB process after pressing under static field. Another embodiment involves a cutting, reorientation, stacking, and gluing process after annealing. Additionally, the invention presents a two-step magnetizing process before completing the CPM manufacturing process.

The present invention relates to an electromagnetic data storage device comprising a data storage medium including a magnetic material, and a write head including an electromagnetic element operable to generate a magnetic field that impinges on a selected portion of the magnetic material of the data storage medium adjacent the write head, so as to affect the magnetization direction of the selected portion of magnetic material. The electromagnetic element includes a magnetic structure including a matrix material, and a plurality of magnetic nanoparticles held in the matrix material.

A tape head, configured to contact a magnetic tape, at the level of a contact plane, for writing to the tape, in operation is provided. The tape head includes a transducer, the latter being a write element, configured to write to the magnetic tape, in operation. The transducer includes a layered write pole, the latter comprising a set of two or more superimposed layers of distinct materials, the layers superimposed in a direction perpendicular to the contact plane. A saturation magnetization of each of two material layers of the set is between 1.0 to 2.3 Tesla. A contrast between the saturation magnetizations of the two material layers of the set is between 32% and 130%, the contrast defined as 100(B.sub.s,max/B.sub.s,min1), where B.sub.s,max and B.sub.s,min respectively denote a largest one and the smallest one of the saturation magnetizations of the two material layers of the set.