High Refractive Index SiC:H Waveguide Core for Focused Thermal Spot
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for heating storage media in thermally assisted magnetic/optical recording are inefficient in reducing the size of the heated spot, limiting storage density due to inadequate energy focusing techniques.
Innovation Solution
A waveguide with a core layer made of amorphous hydrogenated silicon carbide (SiC:H) or bismuth titanate, which allows for more confined light propagation and a higher refractive index, enabling a more focused thermal spot by increasing the thermal gradient, is used in conjunction with a near-field transducer and light source to direct energy onto the recording media.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If conventional energy focusing methods are used, then the heating process is simple, but the heated spot size is large which limits storage density
Solution Approach 1:
The patent changes the refractive index parameter by using a core layer with higher refractive index than conventional waveguides, which enables tighter light confinement and smaller heated spot size. This parameter change directly addresses the contradiction by reducing spot size while managing the complexity through material selection rather than structural complexity
Solution Approach 2:
The patent employs composite material structure with specific layering (bottom cladding, core, top cladding) where each layer has optimized refractive index properties. This composite approach enables precise control over light propagation and heating focus, achieving smaller spot sizes while maintaining manufacturability through established thin-film deposition techniques
2Area of moving object
If light propagation is more confined to achieve smaller heated spot, then storage density increases, but optical loss may increase
Solution Approach 1:
The patent optimizes the refractive index parameter of the core material to achieve the right balance between light confinement and propagation loss. By carefully selecting materials with appropriate refractive indices, the design confines light sufficiently to reduce spot size while maintaining low optical loss through the waveguide structure
Solution Approach 2:
The patent applies local quality by having different refractive index characteristics in different layers of the waveguide. The core layer has higher refractive index for confinement, while cladding layers have lower refractive index to minimize loss, creating optimal local properties in each region to simultaneously achieve small spot size and low optical loss
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 solution achieves a more focused thermal spot on the recording media, enhancing storage density by efficiently guiding and confining energy within the waveguide, while maintaining low optical loss and corrosion resistance.
Implementation Method 1
the core layer (315) includes a material that has a higher index of refraction than either the top or bottom cladding layers
Implementation Method 2
the propagating or guided electromagnetic planar waveguide mode
Data Source
AI summary
Waveguides that include a top cladding layer; a bottom cladding layer; and a core layer positioned between the top cladding layer and the bottom cladding layer, the core layer including a material having a refractive index of not less than 2.1, for example amorphous hydrogenated silicon carbide (SiC:H), or bismuth titanate. Methods of forming core layers of waveguides are also disclosed.