We hereby propose and theoretically investigate a new scheme for simultaneous generation and manipulation of terahertz (THz) waves through difference frequency generation facilitated by a metasurface-assisted nonlinear leaky waveguide antenna. The proposed structure integrates a nonlinear optical waveguide, composed of multiple Al
In this work, mode conversion and wavefront shaping by integrating a metallic metasurface on top of a planar waveguide are proposed and demonstrated. The metasurface consists of C‐shaped nanoantennas. By controlling the orientation of each nanoantenna, mode conversion and focusing effect for the cross‐polarized electric fields inside the waveguide are achieved. The design and simulation results of 16 scenarios of wideband transverse‐magnetic to transverse‐electric mode converters with the mode purity up to 98%, and on‐chip lenses at the wavelength of 1550 nm are reported. It is worth noting that the dimension of the devices along the propagation direction is only 9.6 µm. This work manifests the potential application of mode division multiplexing systems and on‐chip optical interconnections based on metasurfaces.
more » « less- NSF-PAR ID:
- 10384343
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 10
- Issue:
- 23
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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