title: Bowtie plasmonic quantum cascade laser antenna.
abstract: We report a bowtie plasmonic quantum cascade laser antenna that can confine coherent mid-infrared radiation well below the diffraction limit. The antenna is fabricated on the facet of a mid-infrared quantum cascade laser and consists of a pair of gold fan-like segments, whose narrow ends are separated by a nanometric gap. Compared with a nano-rod antenna composed of a pair of nano-rods, the bowtie antenna efficiently suppresses the field enhancement at the outer ends of the structure, making it more suitable for spatially-resolved high-resolution chemical and biological imaging and spectroscopy. The antenna near field is characterized by an apertureless near-field scanning optical microscope; field confinement as small as 130 nm is demonstrated at a wavelength of 7.0 mum.
authors: Nanfang
authors: N
authors: Yu
authors: Ertugrul
authors: E
authors: Cubukcu
authors: Laurent
authors: L
authors: Diehl
authors: David
authors: D
authors: Bour
authors: Scott
authors: S
authors: Corzine
authors: Jintian
authors: J
authors: Zhu
authors: Gloria
authors: G
authors: Höfler
authors: Kenneth B
authors: KB
authors: Crozier
authors: Federico
authors: F
authors: Capasso