Integrated Terahertz Tunneling Filter

We present a novel in-slab beamforming technique that leverages optical tunneling and leaky-wave phenomena. In this way, a frequency-scanning focused beam is projected into a micro-scale silicon slab, and by collecting this beam at a single point with an inverse flare, an integrated all-intrinsic-silicon filter is realized. This technique holds great potential to realize efficient, broadband, all-dielectric frequency-division multiplexers for terahertz, infrared, and visible-frequency waves.