Matched dielectric slot waveguide as an all-dielectric terahertz magnetic dipole.

We observe that the modal field distribution of a dielectric slot waveguide closely resembles a magnetic dipole antenna. Such an aperture distribution traditionally demands metals, making it ill-suited to high frequencies due to excessive ohmic loss. By terminating a dielectric slot waveguide with a matched free-space interface, a compact all-dielectric radiating magnetic dipole is realized.

In the shadow of the laser phantom needle cross: dynamic air-plasma aperture sheds light on terahertz microscopy.

Two plasma filaments crossing above the target create a subwavelength window for terahertz microscopy that excludes any subwavelength probe in vicinity.

Half-Maxwell fisheye lens with photonic crystal waveguide for the integration of terahertz optics.

Currently, optics such as dielectric lenses and curved reflector dishes are commonplace in terahertz laboratories, as their functionality is of fundamental importance to the majority of applications of terahertz waves. However, such optics are typically bulky and require manual assembly and alignment. Here we seek to draw inspiration from the field of digital electronics, which underwent rapid acceleration following the advent of integrated circuits as a replacement for discrete transistors.

Insulator-metal transition in substrate-independent VO thin film for phase-change devices.

Vanadium has 11 oxide phases, with the binary VO presenting stimuli-dependent phase transitions that manifest as switchable electronic and optical features. An elevated temperature induces an insulator-to-metal transition (IMT) as the crystal reorients from a monoclinic state (insulator) to a tetragonal arrangement (metallic). This transition is accompanied by a simultaneous change in optical properties making VO a versatile optoelectronic material.

Demonstration of a highly efficient terahertz flat lens employing tri-layer metasurfaces.

We demonstrate a terahertz flat lens based on tri-layer metasurfaces allowing for broadband linear polarization conversion, where the phase can be tuned through a full 2π range by tailoring the geometry of the subwavelength resonators. The lens functionality is realized by arranging these resonators to create a parabolic spatial phase profile. The fabricated 124-μm-thick device is characterized by scanning the beam profile and cross section, showing diffraction-limited focusing and ∼68% overall efficiency at the operating frequency of 400 GHz.

Analysis of 3D-printed metal for rapid-prototyped reflective terahertz optics.

We explore the potential of 3D metal printing to realize complex conductive terahertz devices. Factors impacting performance such as printing resolution, surface roughness, oxidation, and material loss are investigated via analytical, numerical, and experimental approaches. The high degree of control offered by a 3D-printed topology is exploited to realize a zone plate operating at 530 GHz.

Terahertz Magnetic Mirror Realized with Dielectric Resonator Antennas.

Single-crystal silicon is bonded to a metal-coated substrate and etched in order to form an array of microcylinder passive terahertz dielectric resonator antennas (DRAs). The DRAs exhibit a magnetic response, and hence the array behaves as an efficient artificial magnetic conductor (AMC), with potential for terahertz antenna and sensing applications.