Optical Black Hole Permittivity Profile for Omnidirectional EM Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current materials and structures fail to achieve 100% absorption of electromagnetic energy across all angles and a broad bandwidth, limiting their application in optoelectronic devices, thermal sources, and solar energy harvesting.
Innovation Solution
A material system with spatially varying permittivity, where the permittivity varies inversely with the square of the local radius of curvature, creating an 'effective permittivity potential' that traps electromagnetic energy, converting it into electrical or thermal forms without loss, forming an 'optical black hole' for efficient omnidirectional energy capture.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional materials and structures are used, then manufacturing and operation are simple, but absorption efficiency of electromagnetic energy is insufficient and cannot achieve 100% across all angles and broad bandwidth
Solution Approach 1:
The patent applies local quality by creating a material structure where permittivity varies spatially according to a specific functional form (inverse square of radial distance from center of curvature). This spatially varying permittivity profile is designed to create an effective potential that guides electromagnetic energy toward the center, achieving near-perfect absorption. Different regions of the material have different permittivity values, with the variation following the function ε(r) ∝ 1/r², which creates the desired energy concentration effect without requiring complex multi-layer structures.
2Loss of energy
If spatially varying permittivity structure is implemented, then absorption efficiency improves to nearly perfect, but manufacturing precision requirements increase
Solution Approach 1:
The patent employs parameter changes by systematically varying the permittivity parameter across the material structure according to a specific mathematical function (inverse square law). Rather than using complex geometric variations or multi-layer constructions, the solution changes the electromagnetic parameter (permittivity) itself as a function of position. This approach simplifies manufacturing because it requires controlling a single material parameter (permittivity distribution) rather than precisely assembling multiple geometric components, and the functional form provides a clear design target for fabrication.
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 system achieves nearly perfect absorption efficiency, capturing electromagnetic energy from all directions and converting it into electrical or thermal energy, suitable for diverse applications including solar energy harvesting and optoelectronics.
Implementation Method 1
The system achieves nearly perfect absorption efficiency, capturing electromagnetic energy from all directions and converting it into electrical or thermal energy
Implementation Method 2
A material system with spatially varying permittivity, where the permittivity varies inversely with the square of the local radius of curvature
Data Source
AI summary
An electromagnetic black hole may be fabricated as concentric shells having a permittivity whose variation is at least as great as an inverse square dependence on the radius of the structure. Such a structure concentrates electromagnetic energy incident thereon over a broad range of angles to an operational region near the center of curvature of the structure. Devices or materials may be placed in the operational region so as to convert the electromagnetic energy to electrical signals or to heat. Applications included solar energy harvesting and heat signature detectors.