Trapped spoof surface plasmons with structured defects in textured closed surfaces

Wu, Hong‐Wei; Chen, Hua-Jun; Fan, Huiying; Li, Yang; Fang, Xianwen

doi:10.1364/ol.42.000791

Cited by 16 publications

(8 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The scattering at defects on surfaces or rough surfaces are well studied for nanometer scaled defects and roughness at optical frequencies 21 . The properties of defect rich spoof plasmonic surfaces, however, have not been previously studied, as many spoof plasmonic experiments are conducted at microwave frequencies where no unintended defects due to manufacturing tolerances occur and defects are usually well defined and intended 22,23 . As a first approximation, the defects can be regarded as metallic spheres and as the THz radiation propagates in the plane of the sample surface only, the well-known case of Mie scattering on a metal cylinder applies 24 .…”

Section: Resultsmentioning

confidence: 99%

Scattering of spoof surface plasmon polaritons in defect-rich THz waveguides

Klein

Basden

Hammler

et al. 2019

Sci Rep

View full text Add to dashboard Cite

We report on the first observation of ‘Spoof’ Surface Plasmon Polariton (SPP) scattering from surface defects on metal-coated 3D printed, corrugated THz waveguiding surfaces. Surface defects, a result of the printing process, are shown to assist the direct coupling of the incident free-space radiation into a spoof SPP wave; removing the need to bridge the photon momentum gap using knife-edge or prism coupling. The free space characteristics, propagation losses and confinement of the spoof SPPs to the surface are measured, and the results are compared to finite-difference time domain simulations. Angular resolved THz spectroscopy measurements reveal the scattering patterns from surfaces and are compared with Mie theory, taking into account the shortened wavelength of the photons in their bound SPP state compared to their free space wavelength. These results confirm yet another similarity between the properties of THz spoof SPPs and their natural, non-spoof, counterparts at optical and infrared frequencies which also, unexpectedly, adds functionality to the structures.

show abstract

Section: Resultsmentioning

confidence: 99%

Scattering of spoof surface plasmon polaritons in defect-rich THz waveguides

Klein

Basden

Hammler

et al. 2019

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Moreover, to obtain the localized field enhancement in the THz region, the concept of spoof localized surface plasmons (LSPs) based on the textured perfect electric conductor (PEC) cylinder has been proposed to mimic the metallic nanoparticles supporting the LSPs in optical frequencies . Since then, extensive theoretical and experimental works have been performed to verify the existence of spoof LSPs in various textured metallic structures − which can localize the electric field. Particularly, a three-dimensional textured PEC cylinder with finite thickness has also been experimentally demonstrated to support not only electric LSPs, but also magnetic LSPs at deep subwavelength volumes .…”

Section: Introductionmentioning

confidence: 99%

Strong Purcell Effect for Terahertz Magnetic Dipole Emission with Spoof Plasmonic Structure

Chen

et al. 2019

ACS Appl. Nano Mater.

Self Cite

View full text Add to dashboard Cite

The magnetic Purcell effect is usually described as a modification of the magnetic dipole emission with a resonator. In an optical spectrum, various metallic and dielectric structures have been proposed to enhance the magnetic dipole emission. However, the enhancement of magnetic dipole emission by a well-designed structure has not been extensively investigated in the terahertz spectrum. Here, we propose a spoof plasmonic structure to enhance strongly the magnetic dipole emission by controlling the electromagnetic environment in the terahertz spectrum. The spoof plasmonic structure with deep-subwavelength scale is designed by periodically inserting metallic strips into a hollow silicon cylinder to obtain the “hot spot” of the localized magnetic field in the structural hollow. The resonant frequency and intensity of the magnetic dipole mode supported in this structure can be tuned freely by tailoring the structural parameters. In this context, we investigate the enhancement of a magnetic dipole emission by putting a magnetic dipole at the hollow of the spoof plasmonic structure. The results indicate that the Purcell factor can be more than 103 for a magnetic dipole emission, which is 1 order of magnitude larger than the hollow bare silicon cylinder case. We furthermore investigate the dependence of the Purcell factor on the structural parameters. The spoof plasmonic structure provides the unique ability to enhance the emission from terahertz magnetic dipoles, opening new avenues for novel magnetic light-matter interactions in the terahertz region.

show abstract

“…Multipolar spoof LSPs on the ultrathin planar metal disk have been experimentally demonstrated and used for sensing [23]. Different kinds of passive spoof plasmonic resonator have been proposed to increase the field confinements to improve the sensitivity [24][25][26][27][28][29][30][31][32][33][34], including Fano resonant metasensors [27], hyperbolic sensors [28,29], toroidal metasensors [30][31][32], effective LSPs [33], etc. However, substantial radiative and non-radiative losses in the spoof plasmonic resonators have significantly restricted the sensitivity.…”

Section: Introductionmentioning

confidence: 99%

Ultra-high resolution sensing of glucose concentration based on amplified half-integer localized surface plasmons mode

Zhao

Zhou

Cai

et al. 2019

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Since the half-integer order localized surface plasmons mode is more sensitive to the change of the surrounding materials, an active spoof plasmonic microfluidic sensor using the mode for detecting minute change of glucose aqueous solutions has been proposed at microwave frequencies. By introducing an active coupling circuit near the slit of the spoof plasmonic resonator, the measured quality factor of the half integer order mode (n = 1.5) for the active spoof plasmonic resonator is increased from 148 to 40 000 and the dephasing time is increased to about 16.5 µs when the optimal bias voltage is applied, compared to the passive spoof plasmonic resonator. The resonance frequency changes from 2.45 GHz to 1.74 GHz, with a frequency shift of 710 MHz, when the microfluidic channel is filled with distilled water (about 12 µl). The experiments show that the resonance frequency increases almost linearly with the concentration of the glucose solution. The limit of detection of the active sensor is 9 mg dl −1 . The figure of merit reaches 2236 MHz/(mg/dl). The high-resolution active spoof plasmonic sensor could find more potential applications for biological and chemical sensing.

show abstract

Trapped spoof surface plasmons with structured defects in textured closed surfaces

Cited by 16 publications

References 25 publications

Scattering of spoof surface plasmon polaritons in defect-rich THz waveguides

Scattering of spoof surface plasmon polaritons in defect-rich THz waveguides

Strong Purcell Effect for Terahertz Magnetic Dipole Emission with Spoof Plasmonic Structure

Ultra-high resolution sensing of glucose concentration based on amplified half-integer localized surface plasmons mode

Contact Info

Product

Resources

About