A system for transition curvature improvement on thermally assisted magnetic recording, includes: an energy source, a thermally assisted magnetic recording head including a magnetic main pole for writing of a thermally assisted magnetic recording medium, a waveguide for directing an energy produced by the energy source, and a PPG including a peg and adjacent to the waveguide, the PPG being for turning the energy into a surface plasmon which travels down the peg to heat the thermally assisted magnetic recording medium. The magnetic main pole includes a first portion enabling a first magnetic field strength and at least one additional portion enabling a magnetic field strength stronger than the first magnetic field strength such that a magnetic field of the magnetic main pole along a horizontal direction thereof enables generation of a substantially straight transition curve while writing on the thermally assisted magnetic recording medium.

The card reader includes a peak detector that detects a peak point of a reproduced signal according to a threshold. The peak detector applies, to a first peak value to be determined, a second peak value immediately before the first peak value, a third peak value, which is the second preceding peak value with respect to the first peak value, and a next peak value. When a difference between a first intermediate value, which is a value between the third peak value and the second peak value, and a second intermediate value, which is a value between the second peak value and the first peak value, is greater than or equal to a first difference value, the peak detector ignores a first threshold, and decides the first peak value after confirming that a digital value corresponding to the next peak value has exceeded a second threshold.

A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a spin torque oscillator (STO) element. The data storage device further comprises a differential amplifier comprising a first input coupled to a first end of the STO element and a second input coupled to a second end of the STO element. A bias current is applied to the STO element, and the bias current is adjusted. A resistance delta of the STO element is detected based on an output of the differential amplifier, wherein the resistance delta corresponds to a bias current level when the STO begins to oscillate.

A magnet structure for a magnetic data storage medium erasing apparatus includes a first half comprising a first plurality of magnets arranged symmetrically, having polarization direction of adjacent magnets in quadrature and at an oblique angle with respect to a plane of symmetry. A second half comprises a second plurality of magnets arranged symmetrically, having polarization direction of adjacent magnets in quadrature and at an oblique angle with respect to the plane of symmetry. The second half is arranged symmetrically with respect to the first half, wherein the first half and the second half are separated by an air gap disposed about the plane of symmetry.

Bottom tracks are written to a recording medium using a first setting of a spin-torque oscillator of a single microwave assisted magnetic recording (MAMR) head. Top tracks are written interlaced between and partially overlapping the bottom tracks using the single MAMR head at a second setting of the MAMR head, the first and second settings resulting in different bit aspect ratios for the top and bottom tracks.

A method for starting hard disks, applied in an electronic device, the method includes: starting a storage in the electronic device, and the storage comprising hard disks and a backplane extension chip; sending preset request signals by the hard disks to the backplane extension chip; verifying a number of the hard disks by the backplane expansion chip according to the request signals; when the number of the hard disks is verified successfully, performing type verification on the hard disks by the backplane expansion chip; and sending a start signal by the backplane expansion chip to the target hard disks having a successful type verification according to a preset start sequence and a preset number of the hard disks, to start the target hard disks.

According to one embodiment, a magnetic recording device includes a magnetic head and a controller. The magnetic head includes first and second magnetic poles, a magnetic element provided between the first magnetic pole and the second magnetic pole, first and second terminals electrically connected to one end and another end of the magnetic element, respectively, and a coil. The controller is electrically connected to the magnetic element and the coil, and performs a recording operation. In the recording operation, the controller supplies a recording current to the coil while applying an element voltage between the first and second terminals. When the applied voltage is changed while the recording current is supplied, a differential resistance of the magnetic element becomes a first differential resistance peak when the applied voltage is a first voltage, and becomes a second differential resistance peak when the applied voltage is a second voltage.

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnetic recording layer on a magnesium oxide-titanium oxide (MTO) underlayer, where the MTO underlayer includes an additive material that chemically bonds with titanium. In some examples, the additive material includes iron-oxide, iron, carbon, or various aluminum oxides. By providing the additive material to the MTO that chemically bonds with the titanium of the MTO, diffusion of titanium from the MTO underlayer into the magnetic recording layer is mitigated to provide an improved recording layer that achieves improved areal densities. In some embodiments, an additional magnesium oxide-nitrogen underlayer is also provided, which may include more of the additive material.

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnetic recording layer on a magnesium oxide-titanium oxide (MTO) underlayer, where the MTO underlayer includes an additive material that chemically bonds with titanium. In some examples, the additive material includes iron-oxide, iron, carbon, or various aluminum oxides. By providing the additive material to the MTO that chemically bonds with the titanium of the MTO, diffusion of titanium from the MTO underlayer into the magnetic recording layer is mitigated to provide an improved recording layer that achieves improved areal densities. In some embodiments, an additional magnesium oxide-nitrogen underlayer is also provided, which may include more of the additive material.

A detection device includes a processing device and a storage medium. An ideal waveform signal indicating an ideal waveform of a servo pattern signal which is a result of reading a servo pattern recorded in a servo band of a magnetic tape by a servo reading element is stored in advance in the storage medium. The processing device acquires a servo band signal which is a result of reading the servo band by the servo reading element, and detects the servo pattern signal by comparing the servo band signal with the ideal waveform signal.