共查询到20条相似文献,搜索用时 0 毫秒
1.
Enhanced transmission through subwavelength metallic coaxial apertures by excitation of the TEM mode
F.I. Baida 《Applied physics. B, Lasers and optics》2007,89(2-3):145-149
We present here the first theoretical demonstration of enhanced transmission (up to 90%) through annular aperture arrays engraved
into opaque metallic plates thanks to the excitation of the TEM guided mode inside each coaxial cavity. The generation of
this peculiar mode is obtained, first, by illuminating the structure under oblique incidence and, second, by considering a
TM polarization. Analytical demonstration is performed to confirm the involvement of these two conditions for the emergence
of this guided mode. The originality of this configuration comes, first, from the fact that the TEM mode has no cut-off wavelength
and, second, from the fact that the transmission peak position is independent of the angle of incidence.
PACS 42.25.Fx; 78.20.Bh; 78.67.-n 相似文献
2.
Beruete M Sorolla M Campillo I Dolado JS Martín-Moreno L Bravo-Abad J García-Vidal FJ 《Optics letters》2004,29(21):2500-2502
We explore, both experimentally and theoretically, the existence in the millimeter-wave range of the phenomenon of extraordinary light transmission through arrays of subwavelength holes. We have measured the transmission spectra of several samples made on aluminum wafers by use of an AB Millimetre quasi-optical vector network analyzer in the wavelength range 4.2-6.5 mm. Clear signals of the existence of resonant light transmission at wavelengths close to the period of the array appear in the spectra. 相似文献
3.
Chan HB Marcet Z Woo K Tanner DB Carr DW Bower JE Cirelli RA Ferry E Klemens F Miner J Pai CS Taylor JA 《Optics letters》2006,31(4):516-518
We present measurements of transmission of infrared radiation through double-layer metallic grating structures. Each metal layer contains an array of subwavelength slits and supports transmission resonance in the absence of the other layer. The two metal layers are fabricated in close proximity to allow coupling of the evanescent field on individual layers. The transmission of the double layer is found to be surprisingly large at particular wavelengths, even when no direct line of sight exists through the structure as a result of the lateral shifts between the two layers. We perform numerical simulations using rigorous coupled wave analysis to explain the strong dependence of the peak transmission on the lateral shift between the metal layers. 相似文献
4.
《Physics letters. A》2005,344(6):451-456
By using FDTD numerical simulations, we show that mechanism that is different from surface plasmon polaritons set up by the periodicity at the in-plane metal surfaces may account for the superenhanced light transmission through coaxial hole arrays. We propose that resonant cavity-enhanced light transmission is responsible for it. When an axis is introduced into a hole, slits of definite length are formed. We suppose that a coaxial hole will support the standing waves of Fabry–Pérot-like modes with frequency higher than its cutoff frequency if its gap is small enough in comparison to the wavelength of the incident light and if the metal film is thick enough. 相似文献
5.
The ultrasonic transmission through plates perforated with 2 × 2 or 3 × 3 square array of subwavelength holes per unit cell are studied by numerical simulations. Calculations are obtained by means of a theoretical model under the rigid-solid assumption. It is demonstrated that when the inter-hole distance within the unit cell is reduced, new transmission dips appear resulting from Wood anomalies that have influence on the second and the third order Fabry-Perot peak. When the inter-hole distance within the unit cell is reduced, the transmission spectrum of the multiple-sublattice holes arrays tends to the transmission spectrum of a plate perforated with only one hole in the unit cell. 相似文献
6.
Numerical investigation of the optical transmission through the one-dimensional subwavelength metallic cavity arrays (SMCA) is presented. Based on the finite-difference time-domain technique, we discuss the influence of the structural parameters on the transmission spectrum. The transmission peaks are attributed to the Fabry-Perot resonance; and the transmission dips are attributed to the surface plasmon resonance. For the SMCA with two cavities in one unit, the redshift of the transmission peak with increasing the distance between the two cavities originates from the depression of the coupling strength. These results obtained here will be helpful to design the plasmonic frequency-selecting device. 相似文献
7.
We present experimental results of the transmission magnitude and phase change of terahertz pulses through thin metallic films patterned with subwavelength hole arrays on silicon wafers. Terahertz time-domain spectroscopy measurements reveal a sharp phase peak centered on the surface plasmon resonance. Correspondingly, and consistent with the Kramers-Kronig relations, the measured transmission magnitude has the shape of the derivative of this peak. In addition, we determine that the aperture shape has a notable effect on the transmission properties of two-dimensional hole arrays. 相似文献
8.
9.
Resonant terahertz transmission in subwavelength metallic hole arrays of sub-skin-depth thickness 总被引:2,自引:0,他引:2
We study surface-plasmon-enhanced terahertz transmission through subwavelength metallic hole arrays of sub-skin-depth thickness. Dynamic evolution of surface-plasmon resonance in terms of array thickness is characterized by use of terahertz time-domain spectroscopy in the frequency range 0.1-4.5 THz. A critical thickness of lead array film is observed, above which surface-plasmon coupling of terahertz pulses begins and is enhanced rapidly as the array thickness is increased toward the skin depth. The experimental results indicate that high-efficiency extraordinary terahertz transmission can be achieved at an array thickness of only one third of skin depth. 相似文献
10.
The optical transmission through a subwavelength aperture in a metal film is strongly enhanced when the incident light is resonant with surface plasmons at the corrugated metal surface surrounding the aperture. Conversely, the aperture acts as a novel probe of the surface plasmons, yielding useful insights for optimizing the transmission enhancement. For the optimal corrugation geometry, a set of concentric circular grooves, three times more light is transmitted through the central subwavelength aperture than directly impinges upon it. This effect is useful in the fabrication of near-field optical devices with extremely high optical throughput. 相似文献
11.
Y. Pang 《Optics Communications》2007,280(1):10-15
Transmission of polarized light through subwavelength slit apertures is studied in visible and near infrared range wavelengths. We examine the roles played by the slit apertures, such as length, depth, period and number of slits. The experiment results, including dispersion curves, demonstrate among other things that the surface plasmon polariton and Fabry-Perot waveguide modes collectively dictate the transmission properties of subwavelength slit arrays and that as they approach each other, not only large gaps are formed but also mode interconversion occurs. These findings are discussed and compared to theoretical predictions. 相似文献
12.
Martín-Moreno L García-Vidal FJ Lezec HJ Pellerin KM Thio T Pendry JB Ebbesen TW 《Physical review letters》2001,86(6):1114-1117
We present a fully three-dimensional theoretical study of the extraordinary transmission of light through subwavelength hole arrays in optically thick metal films. Good agreement is obtained with experimental data. An analytical minimal model is also developed, which conclusively shows that the enhancement of transmission is due to tunneling through surface plasmons formed on each metal-dielectric interface. Different regimes of tunneling (resonant through a "surface plasmon molecule," or sequential through two isolated surface plasmons) are found depending on the geometrical parameters defining the system. 相似文献
13.
Enhanced transmission through periodic arrays of subwavelength holes: the role of localized waveguide resonances 总被引:1,自引:0,他引:1
By using the rigid full-vectorial three-dimensional finite-difference time-domain method, we show that the enhanced transmission through a metallic film with a periodic array of subwavelength holes results from two different resonances: (i) localized waveguide resonances where each air hole can be considered as a section of metallic waveguide with both ends open to free space, forming a low-quality-factor resonator, and (ii) well-recognized surface plasmon resonances due to the periodicity. These two different resonances can be characterized from electromagnetic band structures in the structured metal film. In addition, we show that the shape effect in the enhanced transmission through the Au film with subwavelength holes is attributed to the localized waveguide resonance. 相似文献
14.
We present finite difference time domain simulations of the enhancement of the optical transmission through a single subwavelength slit in a thick metal film caused by resonances of the electromagnetic fields in and near the slit. These can be enhanced by including a periodic modulation on the in-coupling surface, and the dependence of the transmission on the grating structural parameters is analysed in detail. 相似文献
15.
We observe and theoretically analyze the plasmonic analog of the critical angle phenomenon in optical transmission through subwavelength gratings milled in an optically thick metal film. The total transmission from a denser medium to a less dense one vanishes while the total reflection holds very strong, providing the incidence angle increases past the plasmonic critical angle (PCA). The conditions and physical origins of the total internal reflection above the PCA are clarified. 相似文献
16.
We demonstrate the phenomenon of nonreciprocal extraordinary optical transmission (NEOT) through metallic film with slits on the substrate of magneto-optical materials. Under uniformly magnetization, the system can show nonreciprocal transmission at near-IR frequency range. With a properly designed structure, the nonreciprocity can be as high as 57.6%. Numerical evidence shows that the nonreciprocal performance is sensitive to the incidence angle, as well as to the thickness of the substrate. 相似文献
17.
Control of optical transmission through metals perforated with subwavelength hole arrays 总被引:3,自引:0,他引:3
The transmission spectrum of a metal that is perforated with a periodic array of subwavelength holes exhibits well-defined maxima and minima resulting from, respectively, a transmission enhancement by surface plasmons and Wood's anomaly, a diffraction effect. These features occur at wavelengths determined by the geometry of the hole arrays, the refractive index of the adjacent medium, and the angle of incidence. We demonstrate control of the transmission through variation of these parameters and show that perforated metal films may form a novel basis for electro-optic devices such as flat-panel displays, spatial light modulators, and tunable optical filters. 相似文献
18.
We propose a square-core metallic nanotube array and investigate its optical transmission property theoretically. We find that the transmission spectra can be tuned by the width of square-core edge, the intertube spacing and the dielectric constants of the core and the embedding medium between the nanotubes. We show that there is a band gap over a wide optical wavelength, and its width, number and position are sensitive to the tunable parameters. We also discuss the situation of the rectangular-core nanotube arrays and present that modification of the size of internal holes leads to redshift of the transmission spectra. Based on the localized nature of the field distributions, we show that there are local plasmonic resonant modes that originate from multipolar plasmon polaritons and a large number of opposing surface charges build up in the gap between adjacent nanotubes. 相似文献
19.
20.
Superenhanced light transmission through subwavelength rectangular hole
arrays have been reported and some investigations have been made into the
physical origin of this phenomenon [K.J. Klein Koerkamp et al., Phys. Rev. Lett.
92, 183901 (2004)]. In our current work, by performing FDTD (finite
difference in the time domain) numerical simulations, we demonstrate that
mechanism that is different from surface plasmon polaritons set up by the
periodicity at the in-plane metal surfaces may account for this
superenhanced light transmission. We suggest that for arrays of rectangular
holes with small enough width in comparison to the wavelength of the
incident light, standing electromagnetic fields can be set up inside the
cavity by the surface plasmons on the hole walls with its intensity being
substantially enhanced inside the cavity. So resonant cavity-enhanced light
transmission is predominant and responsible for its superenhanced light
transmission. Rectangular holes behave as Fabry-Pérot resonance cavities
except that the frequency of their fundamental modes is restricted by their
TM cutoff frequency. However we believe that both localized surface plasmon
modes and surface plasmon polaritons set up by the periodicity at the
in-plane metal surfaces have their shares in extraordinary optical
transmission of rectangular hole arrays especially when the width of the
rectangular hole is not small enough and the metal film is not thick enough. 相似文献