Guided-Wave Metasurfaces for Light Extraction and Molding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional photonic integrated circuits (PICs) face limitations in controlling light when converting between guided and free-space modes, with edge couplers and surface gratings providing limited functionalities and lacking complete control over light, while metasurfaces driven by free-space light make it difficult to integrate light sources on a chip.
Innovation Solution
A hybrid photonic component using integrated photonics and metasurfaces driven by guided waves, where subwavelength-sized meta-atoms are placed on top of waveguides to bridge guided and free-space light waves, allowing for the extraction and molding of light into desired free-space fields, eliminating high-order diffraction loss and enabling denser on-chip integration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional edge couplers and surface gratings are used for light conversion between guided and free-space modes, then the system structure is simple, but the light control functionality is limited and incomplete
Solution Approach 1:
The patent combines waveguides with metasurfaces to create a hybrid structure that integrates the light guiding capability of waveguides with the advanced light manipulation capabilities of metasurfaces. This merging enables complete control over light waves during mode conversion while maintaining a relatively compact structure.
Solution Approach 2:
The invention uses composite structures combining dielectric waveguide materials with metasurface materials (such as metal-dielectric-metal nano-bar antennas). This composite approach enables simultaneous achievement of light guidance and sophisticated light field control that neither component could achieve alone.
2Adaptability or versatility
If metasurfaces are driven by free-space light to generate free-space functions, then the light control capability is enhanced, but the integration of light sources on chip becomes difficult
Solution Approach 1:
Instead of driving metasurfaces with free-space light as in conventional systems, the patent inverts the approach by driving metasurfaces with guided light from waveguides. This inversion enables direct integration with on-chip light sources while maintaining the advanced light control capabilities of metasurfaces.
Solution Approach 2:
The waveguide acts as an intermediary that couples on-chip light sources to the metasurface. This intermediary structure enables efficient transfer of light from the waveguide to the metasurface, facilitating integration while preserving the metasurface's light manipulation capabilities.
3Productivity
If conventional surface gratings are used for light extraction, then the device structure is simple, but high-order diffraction loss occurs and on-chip integration density is reduced
Solution Approach 1:
The metasurface consists of subwavelength-sized meta-atoms with locally optimized geometric parameters (size, shape, orientation) that are specifically designed to control the phase, amplitude, and polarization of extracted light. This local optimization eliminates high-order diffraction losses while enabling dense integration.
Solution Approach 2:
The invention changes the fundamental parameters of the light extraction structure from conventional grating geometries to subwavelength meta-atom geometries. By controlling the geometric parameters of individual meta-atoms, the system achieves precise control over light extraction with minimal diffraction loss and high integration density.
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 provides complete control over light waves, enabling complex free-space functions such as beam deflection and focusing, and allows for the direct emission of orbital angular momentum (OAM) lasers on a chip, overcoming the limitations of existing technologies by leveraging the synergistic combination of integrated photonics and metasurfaces.
Implementation Method 1
light waves being guided by the waveguide to be extracted into free-space and molded into desired light fields
Implementation Method 2
Each meta-atom within the periodic arrangement can impose a predetermined phase shift on a light wave being guided through the waveguide
Implementation Method 3
The evanescent tail of the guided light wave can induce a first electric dipole via bottom cuboids in the sandwich nano-bar antenna
Implementation Method 4
The first and second dipoles generate a magnetic dipolar resonance. The first and second dipoles and the magnetic dipolar resonance generate a directional radiation
Implementation Method 5
the plurality of supercells can generate a well-defined topological charge when a light wave is guided through the waveguide
Data Source
AI summary
Embodiments relate to a photonic component having a metasurface. The metasurface includes a substrate with a thin-layer of meta-atoms disposed thereon. The photonic component includes a waveguide having a top surface, wherein the metasurface is disposed on at least a portion of the top surface such that the meta-atoms form an array on the top surface. The photonic component includes a sandwich nano-bar antenna formed in or on the metasurface.