Electro-Optical Modulator Pulsed Laser for EAMR Thermal Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional energy-assisted magnetic recording (EAMR) disk drives face challenges in power consumption control, leading to overheating and deformation of near-field transducers, as well as inadequate lateral thermal gradients, resulting in wider track widths during recording.
Innovation Solution
The implementation of an electro-optical modulator (EAM) coupled with the laser to provide a pulsed energy output, which modulates the laser's current to reduce power consumption and mitigate overheating, while maintaining high-density recording capabilities by focusing energy with surface plasmons.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a constant power signal is provided to the laser during writing, then the laser provides a constant source of energy to heat small regions of the media, but power consumption increases and the near-field transducer overheats and deforms
Solution Approach 1:
The patent applies periodic action by pulsing the laser diode instead of providing constant power. The controller activates the laser diode in periodic pulses during the writing operation, which heats the media only during these pulse intervals. This periodic heating achieves the necessary temperature for magnetic recording while allowing cooling intervals that prevent transducer overheating and reduce overall power consumption.
2Reliability
If a constant power signal is provided to the laser during writing, then the laser remains on throughout the write operations, but the near-field transducer overheats, deforms, melts, or corrodes
Solution Approach 1:
The patent implements periodic action by controlling the laser diode to operate in pulsed mode rather than continuously. The controller switches the laser diode on and off in periodic intervals, which directly reduces the thermal load on the near-field transducer. This periodic operation prevents the transducer from accumulating excessive heat that would cause deformation, melting, or corrosion, thereby improving transducer reliability and lifespan.
3Temperature
If the lateral thermal gradient in the media is lower than desired, then the temperature of the media does not fall off sufficiently quickly in the cross track direction, but the track widths recorded become wider than desired
Solution Approach 1:
The patent applies periodic action through pulsed laser heating, which creates more pronounced thermal gradients in the media. The intermittent heating allows heat to dissipate laterally between pulses, resulting in a steeper temperature fall-off in the cross-track direction. This enhanced lateral thermal gradient confines the heated region more tightly, producing narrower and more precise track widths during magnetic recording.
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
This solution enhances the reliability and performance of EAMR disk drives by reducing power consumption, minimizing overheating issues, and achieving narrower track widths through improved thermal gradient control, thereby improving the overall recording density and precision.
Implementation Method 1
The laser 14 provides a constant source of energy, which is used to heat small regions of the media 18
Implementation Method 2
at least one electro-optical modulator (EAM) optically coupled with the laser(s)
Data Source
AI summary
A method and system provide an energy assisted magnetic recording (EAMR) disk drive. The EAMR disk drive includes a media, at least one laser coupled with the slider, at least one EAMR head on the slider, and at least one electro-optical modulator (EAM) The EAM(s) are optically coupled with the laser(s) and coupled with the slider. The combination of the laser(s) and EAM(s) provide a pulsed energy output. The EAMR head(s) include at least one waveguide, a write pole, and at least one coil for energizing the write pole. The waveguide(s) receive the pulsed energy output and direct the pulsed energy output toward the media.