Dual Waveguide Heat-Assisted Magnetic Recording
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In thermally assisted magnetic/optical recording, existing technologies face challenges in achieving precise control over the dimensions of data bits and efficient heat management due to the sensitivity of local surface plasmons to the shape and location of near-field transducers, which affects data recording accuracy and efficiency.
Innovation Solution
The apparatus includes a planar waveguide with a metallic structure defining a tapered opening and a multilayer dielectric structure, which focuses electromagnetic waves to a focal region, enhancing light confinement and electric field gradients for improved data bit recording and heat dissipation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a planar solid immersion mirror lens is used to focus electromagnetic waves, then the focused spot size is reduced improving data bit precision, but the heat dissipation becomes insufficient causing temperature management problems
Solution Approach 1:
The device is divided into two separate waveguides: a first waveguide for focusing electromagnetic waves to achieve precise data bit recording, and a second waveguide for extracting heat from the storage medium. This segmentation allows each component to optimize its specific function without compromising the other.
Solution Approach 2:
A dielectric layer acts as an intermediary between the first waveguide (focusing element) and the second waveguide (heat extraction element). This intermediary enables thermal coupling for efficient heat transfer while maintaining optical isolation to preserve the focusing capability and prevent interference with the electromagnetic wave focus.
2Manufacturing precision
If the near-field transducer shape and location are adjusted to improve data bit dimensions, then recording precision is improved, but the system complexity increases due to sensitivity requirements
Solution Approach 1:
The system separates the functions of focusing and heat extraction into distinct waveguides, eliminating the need for complex near-field transducer structures. The first waveguide handles focusing with simple geometric optics, while the second waveguide manages thermal effects, reducing overall system complexity.
Solution Approach 2:
The patent replaces the complex near-field optical transducer system with a simpler two-waveguide configuration using geometric optics for focusing and thermal conduction for heat management. This substitution eliminates sensitive plasmonic structures while achieving comparable or superior performance.
3Productivity
If light absorption in the near-field transducer is increased to improve recording efficiency, then energy utilization is improved, but heat generation increases requiring cooling mechanisms
Solution Approach 1:
The patent converts the harmful heat generated by light absorption in the first waveguide into a useful function by using the second waveguide to extract and utilize this heat for thermal assistance in the storage medium. The waste heat becomes a resource that improves recording efficiency.
Solution Approach 2:
The two waveguides are positioned in close proximity and coupled through a dielectric layer, merging the optical focusing function with thermal management in a single integrated device structure. This combination allows simultaneous optimization of both recording precision and heat dissipation.
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 configuration compresses the focused spot by a significant factor, increasing data bit precision and recording efficiency while effectively managing heat, thereby enhancing the overall performance of thermally assisted magnetic/optical recording systems.
Implementation Method 1
a first waveguide configured to focus an electromagnetic wave to a focal region
Implementation Method 2
The PSIM directs light onto the near-field transducer to form a local surface plasmon (LSP). A high electric field surrounding the near-field transducer appears, due to collective oscillations of electrons in the metal. Part of this field will tunnel into an adjacent storage medium and get absorbed, raising the temperature of the medium locally for recording.
Implementation Method 3
Light is absorbed in the near-field transducer, creating heat that requires a cooling mechanism for its functioning.
Data Source
AI summary
An apparatus includes a first waveguide configured to focus an electromagnetic wave to a focal region, and a second waveguide to further condense the light to an optical spot. The second waveguide includes a metallic structure defining an opening having one end positioned adjacent to the focal region and a multilayer structure positioned in the opening, the multilayer structure including a first layer of dielectric material, and second and third layers of dielectric material positioned on opposite sides of the first layer. A layer of lower index of refraction than that of the first dielectric layer may be positioned adjacent to the inner walls of the opening in the second waveguide to efficiently excite surface plasmons, and propagate them with low loss.