Spin Torque Oscillator Magnetic Head for Low-Heat High-Density Recording
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in achieving high-density magnetic recording is hindered by thermal fluctuations, and existing spin torque oscillators require high current densities to generate sufficient longitudinal high-frequency magnetic fields, leading to heat generation and degradation in performance.
Innovation Solution
A magnetic head assembly incorporating a spin torque oscillator with a Fe—Co—Al alloy, Fe—Co—Si alloy, Fe—Co—Ge alloy, Fe—Co—Mn alloy, or Fe—Co—Cr alloy, featuring a first magnetic layer, a second magnetic layer, and an intermediate layer, designed to operate with low current density while generating a high-intensity longitudinal high-frequency magnetic field.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a spin torque oscillator is used to generate high-frequency magnetic field, then recording density can be increased and thermal fluctuation can be suppressed, but high current density is required which causes heat generation and performance degradation
Solution Approach 1:
The patent changes the material composition of the magnetic layer from conventional materials to specific alloys (Fe-Co-Al, Fe-Co-Si, Fe-Co-Ge, Fe-Co-Mn, or Fe-Co-Cr) to alter the spin torque characteristics. This material parameter change enables the oscillator to generate sufficient high-frequency magnetic field with lower current density, thereby reducing heat generation while maintaining high recording density capability
Solution Approach 2:
The patent employs composite alloy structures combining Fe-Co with additional elements (Al, Si, Ge, Mn, or Cr) to create magnetic layers with optimized properties. These composite materials provide both the necessary spin torque efficiency for low-current operation and the magnetic characteristics required for high-frequency field generation, resolving the contradiction between current density requirements and heat generation
2Power
If high current density is applied to spin torque oscillator, then sufficient longitudinal high-frequency magnetic field can be generated, but heat generation increases and performance degrades
Solution Approach 1:
By changing the material composition to Fe-Co-based alloys with specific additional elements, the patent modifies the spin polarization and spin scattering characteristics of the magnetic layer. This parameter change increases spin torque transmission efficiency, allowing the same magnetic field intensity to be achieved with lower current density, thus maintaining performance stability while avoiding heat-induced degradation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design enables stable oscillation at lower current densities, effectively resonating the magnetic medium and enhancing recording density while minimizing heat generation and maintaining high spin torque transmission efficiency.
Implementation Method 1
magnetization of the magnetic layer generates ferromagnetic resonance by spin torque generated by the spin injection layer
Implementation Method 2
magnetization of the magnetic layer generates ferromagnetic resonance by spin torque generated by the spin injection layer
Implementation Method 3
a high-frequency magnetic field in the vicinity of resonant frequency of the magnetic recording medium which is sufficiently higher than recording signal frequency is applied locally to the medium. As a result, the medium resonates and the coercitivity (Hc) of the medium of a portion where the high-frequency magnetic field is applied decreases
Data Source
AI summary
A magnetic head assembly includes: a magnetic recording head, a head slider, a suspension and an actuator arm. The magnetic recording head includes a spin torque oscillator and a main magnetic pole. The spin torque oscillator includes, a first magnetic layer including at least one selected from the group consisting of a Fe—Co—Al alloy, a Fe—Co—Si alloy, a Fe—Co—Ge alloy, a Fe—Co—Mn alloy a Fe—Co—Cr alloy and a Fe—Co—B alloy, a second magnetic layer, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. The main magnetic pole is placed together with the spin torque oscillator. The magnetic recording head is mounted on the head slider. The head slider is mounted on one end of the suspension. The actuator arm is connected to other end of the suspension.