Abstract
Despite a plethora of applications ranging from wireless communications to sensing and spectroscopy, the current terahertz beam steering technologies suffer from tremendous insert loss, stringent control of electric bias, limited scanning angle, relatively complicated configuration and narrow operation bandwidth, preventing further practical application. We propose and demonstrate a conceptually new approach for terahertz beam steering by virtue of gap plasmon geodesic antennas. By adjusting the geometric dimension of the gap plasmon geodesic antennas, all gap plasmon modes add coherently along a peculiar direction that depends on the geodesic mean surface. Consequently, high directive beams are generated through the antenna, whose direction could be changed within a wide-angle range spanning ±45° by lateral motion of the feed. Furthermore, an assembled antenna structure consisting of four-element geodesic antennas array is proposed for full 360° beam steering, which can operate in a broadband range from 0.8 THz to 1.2 THz.
Highlights
Plasmonic antennas integrated with active media enable the dynamic modulation of the optical properties without compromising the device thickness[15,16,17,18]
Based on a semi-circular curve, we propose a wide field-of-view and broadband terahertz beam steering strategy based on gap plasmon geodesic antenna in this paper
When a small feed with the electric field E perpendicular to the conducting plates is disposed at the end of the semi-circular parallel plate waveguide (PPWG), it will be coupled to the semi-circular PPWG and generates surface plasmon polaritons (SPPs) on the metal surface
Summary
Despite a plethora of applications ranging from wireless communications to sensing and spectroscopy, the current terahertz beam steering technologies suffer from tremendous insert loss, stringent control of electric bias, limited scanning angle, relatively complicated configuration and narrow operation bandwidth, preventing further practical application. We propose and demonstrate a conceptually new approach for terahertz beam steering by virtue of gap plasmon geodesic antennas. Geometric optics are explored to determinate the geometric parameters of the antenna so that spherical wavefront transform into plane wavefront after through the antenna Numerical characterizations in both near-field and far-field demonstrate high directive THz beams are generated, whose direction could be changed within ±45° by shifting the feed along the plasmonic antenna. We show that the scanning range can be further extended to full 360° by a four-element assembled antenna structures and the relative bandwidth exceeds 40% around 1 THz
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
