Details

Autor(en) / Beteiligte

• Kannegulla, Akash
• Cheng, Li-Jing

Titel

Subwavelength focusing of terahertz waves in silicon hyperbolic metamaterials

Ist Teil von

• Optics letters, 2016-08, Vol.41 (15), p.3539-3542

Ort / Verlag

United States

Erscheinungsjahr

2016

Quelle

Optica Publishing Group (OPG)

Beschreibungen/Notizen

• We theoretically demonstrate the subwavelength focusing of terahertz (THz) waves in a hyperbolic metamaterial (HMM) based on a two-dimensional subwavelength silicon pillar array microstructure. The silicon microstructure with a doping concentration of at least 10   cm offers a hyperbolic dispersion at terahertz frequency range and promises the focusing of terahertz Gaussian beams. The results agree with the simulation based on effective medium theory. The focusing effect can be controlled by the doping concentration, which determines the real part of the out-of-plane permittivity and, therefore, the refraction angles in HMM. The focusing property in the HMM structure allows the propagation of terahertz wave through a subwavelength aperture. The silicon-based HMM structure can be realized using microfabrication technologies and has the potential to advance terahertz imaging with subwavelength resolution.