An Ultra-Wideband Leaky Lens Antenna for Broadband Spectroscopic Imaging Applications

TL;DR

This paper introduces a broadband leaky lens antenna designed for spectroscopic imaging in the 300-900 GHz range, demonstrating effective integration with MKID detectors and promising efficiency and bandwidth for future on-chip spectrometers.

Contribution

The paper presents a novel broadband leaky lens antenna integrated with MKID technology, covering a wide frequency range with high efficiency for spectroscopic applications.

Findings

Aperture efficiency of approximately 0.4 across the band

Good agreement between measurements and simulations

Achieves a 1:3 bandwidth suitable for future on-chip spectrometers

Abstract

We present the design, fabrication and characterisation of a broadband leaky lens antenna for broadband, spectroscopic imaging applications. The antenna is designed for operation in the 300-900 GHz band. We integrate the antenna directly into an Al-NbTiN hybrid MKID to measure the beam pattern and absolute coupling efficiency at three frequency bands centred around 350, 650 and 850 GHz, covering the full antenna band. We find an aperture efficiency $\eta_{ap} \approx 0.4$ over the whole frequency band, limited by lens reflections. We find a good match with simulations for both the patterns and efficiency, demonstrating a 1:3 bandwidth in the sub-mm wavelength range for future on-chip spectrometers.