Coherent Detection of Multiband Terahertz Radiation Using a Surface Plasmon-Polariton Based Photoconductive Antenna

We characterize a dipole antenna structure that allows for coherent detection of narrowband terahertz radiation with enhanced sensitivity at the resonant frequency. The antenna incorporates a corrugated metal structure that surrounds the dipole. Each periodically spaced groove in the corrugation couples an approximate replica of the incident THz pulse to a surface plasmon-polariton pulse, which then propagates towards and is detected by the dipole. We use numerical simulations to validate the experimental data. Based on these results, we describe a multiband dipole antenna detector that allows for enhanced sensitivity at multiple frequencies. This device can also be used as an emitter.

[1]  R A Linke,et al.  Enhanced light transmission through a single subwavelength aperture. , 2001, Optics letters.

[2]  N. M. Froberg,et al.  Generation of tunable narrow‐band THz radiation from large aperture photoconducting antennas , 1994 .

[3]  Richard M Osgood,et al.  Enhancing the signal-to-noise ratio of an infrared photodetector with a circular metal grating. , 2008, Optics express.

[4]  Ajay Nahata,et al.  Role of metal film thickness on the enhanced transmission properties of a periodic array of subwavelength apertures. , 2005, Optics express.

[5]  H. Raether.  Surface Plasmons on Smooth and Rough Surfaces and on Gratings , 1988 .

[6]  Ajay Nahata,et al.  Excitation and scattering of surface plasmon-polaritons on structured metal films and their application to pulse shaping and enhanced transmission , 2005 .

[7]  Fujikata Junichi,et al.  Si Nano-Photodiode with a Surface Plasmon Antenna , 2006 .

[8]  K. Cheung,et al.  Picosecond photoconducting Hertzian dipoles , 1984 .

[9]  Hanspeter Helm,et al.  Far-infrared vibrational spectra of all-trans, 9-cis and 13-cis retinal measured by THz time-domain spectroscopy , 2000 .

[10]  Weijia Wen,et al.  Emission of terahertz radiations from fractal antennas , 2009 .

[11]  R A Linke,et al.  Beaming Light from a Subwavelength Aperture , 2002, Science.

[12]  K. Kawase,et al.  Non-destructive terahertz imaging of illicit drugs using spectral fingerprints. , 2003, Optics express.

[13]  Christopher Robert Lawrence,et al.  Enhanced microwave transmission through a single subwavelength aperture surrounded by concentric grooves , 2005 .

[14]  Ajay Nahata,et al.  Controlling the transmission resonance lineshape of a single subwavelength aperture. , 2005, Optics express.

[15]  David B. Rutledge,et al.  Imaging Antenna Arrays , 1981, 1981 International Conference on Submillimeter Waves and Their Applications.

[16]  R. J. Bell,et al.  Optical properties of the metals Al, Co, Cu, Au, Fe, Pb, Ni, Pd, Pt, Ag, Ti, and W in the infrared and far infrared. , 1983, Applied optics.

[17]  P. Maraghechi,et al.  Enhanced THz radiation emission from plasmonic complementary Sierpinski fractal emitters. , 2010, Optics express.

[18]  M. Beruete,et al.  Very low-profile "Bull's Eye" feeder antenna , 2005, IEEE Antennas and Wireless Propagation Letters.

[19]  Ajay Nahata,et al.  Coupling terahertz radiation onto a metal wire using a subwavelength coaxial aperture. , 2007, Optics express.

[20]  Masayoshi Tonouchi,et al.  Cutting-edge terahertz technology , 2007 .