Open AccessTerahertz photoconductive antenna with metal nanoislands
Author(s) -
Sang-Gil Park,
Yong-Je Choi,
Young-Sook Oh,
KiHun Jeong
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.025530
Subject(s) - materials science , terahertz radiation , plasmon , optoelectronics , photoconductivity , optics , antenna (radio) , laser , surface plasmon , surface plasmon polariton , terahertz spectroscopy and technology , physics , telecommunications , computer science
This work presents a nanoplasmonic photoconductive antenna (PCA) with metal nanoislands for enhancing terahertz (THz) pulse emission. The whole photoconductive area was fully covered with metal nanoislands by using thermal dewetting of thin metal film at relatively low temperature. The metal nanoislands serve as plasmonic nanoantennas to locally enhance the electric field of an ultrashort pulsed pump beam for higher photocarrier generation. The plasmon resonance of metal nanoislands was achieved at an excitation laser wavelength by changing the initial thickness of metal film. This nanoplasmonic PCA shows two times higher enhancement for THz pulse emission power than a conventional PCA. This work opens up a new opportunity for plasmon enhanced large-aperture THz photoconductive antennas.