A thermally controlled multiband, mode-switching plasmonic filter with periodic subwavelength metal asterisk-shaped air hole arrays has been proposed in the terahertz range. Utilizing the changing properties to terahertz wave propagating on the metal-semiconductor interface and in the semiconductor InSb at varying temperature, thermally controlled multiband, mode-switching plasmonic filter owns an excellent tuning ability to terahertz wave. The simulation results show that the maximum transmittance of the structure is 99.8% at 434 GHz, 80 K, the bandwidths at 80 K are 56 GHz at 0.434 THz, 14 GHz at 944 GHz and maximum intensity modulation depth could reach to 99.8% at 434 GHz between 80 K and 373 K. 相似文献
A high sensitivity plasmonic temperature sensor based on a side-polished photonic crystal fiber is proposed in this work.In order to achieve high sensitivity and high stability,the gold layer is coated on the side-polished photonic crystal fiber to support surface plasmon resonance.The mixture of ethanol and chloroform is used as the thermosensitive liquid.The performances of the proposed temperature sensor were investigated by the finite element method(FEM).Simulation results indicate that the sensitivity of the temperature sensor is as high as 7.82 nm/℃.It has good linearity(R;=0.99803),the resolution of 1.1×10;℃,and the amplitude sensitivity of 0.1008℃;.In addition,the sizes of the small air hole and polishing depth have little influence on the sensitivity.Therefore,the proposed sensor shows a high structure tolerance.The excellent performance and high structure tolerance of the sensor make it an appropriate choice for temperature measurement. 相似文献
Efficient amplification of spoof surface plasmon polaritons (SPPs) is proposed at microwave frequencies by using a subwavelength‐scale amplifier. For this purpose, a special plasmonic waveguide composed of two ultrathin corrugated metallic strips on top and bottom surfaces of a dielectric substrate with mirror symmetry is presented, which is easy to integrate with the amplifier. It is shown that spoof SPPs are able to propagate on the plasmonic waveguide in broadband with low loss and strong subwavelength effect. By loading a low‐noise amplifier chip produced by the semiconductor technology, the first experiment is demonstrated to amplify spoof SPPs at microwave frequencies (from 6 to 20GHz) with high gain (around 20dB), which can be directly used as a SPP amplifier device. The features of strong field confinement, high efficiency, broadband operation, and significant amplification of the spoof SPPs may advance a big step towards other active SPP components and integrated circuits.
In this research work, we propose all‐optical transistor based on metallic nanoparticle cross‐chains geometry. The geometry of the proposed device consists of two silver nanoparticle chains arranged along the x‐ and z‐axis. The x‐chain contains a Kerr nonlinearity, the source beam is set at the left side of the later, while the control beam is located at the top side of the z‐chain. The control beam can turn ON and OFF the light transmission of an incoming light. We report a theoretical model of a very small all‐optical transistor proof‐of‐conceptmade of optical ‘light switching light'concept. We show that the transmission efficiency strongly depends on the control beam and polarization of the incoming light. We investigate the influence of a perfect reflector and reflecting substrate on the transmission of the optical signal when the control beam is turned ON and OFF. These new findings make our unique design a potential candidate for future highly‐integrated optical information processing chips. 相似文献
Herein,we propose a high-quality(Q) factor hybrid plasmonic nanocavity based on distributed Bragg reflectors(DBRs) with low propagation loss and extremely strong mode confinement.This hybrid plasmonic nanocavity is composed of a high-index cylindrical nanowire separated from a metal surface possessing shallow DBRs gratings by a sufficiently thin low-index dielectric layer.The hybrid plasmonic nanocavity possesses advantages such as a high Purcell factor(Fp) of up to nearly 20000 and a gain threshold approaching 266 cm~(-1)at 1550 nm,promising a greater potential in deep sub-wavelength lasing applications. 相似文献
We investigate a high sensitive chiral molecule detector based on Goos–Hanchen shift(S) in Kretschmann configuration involving chiral tri(diethylene glycol monobutyl) citrates(TDBCs). Fresnel equations and the stationary phase method are employed to calculate S. Due to the interaction between surface plasmon polaritons and chiral TDBCs, S with chiral TDBCs are amplified at near the resonant wavelengths of chiral TDBCs. Our calculation results show that although the difference between the resonant wavelengths of left and right TDBCs is 4.5 nm, the positions of the largest S for the structures with left TDBCs and right TDBCs do not overlap. S reaches 400 times(or 200 times) the incident wavelength around the resonant wavelength of left TDBCs(or right TDBCs). The difference of S with chiral TDBCs(?S) can reach400 times or 200 times the incident wavelength in certain conditions, which can be directly observed in experiments. Left TDBCs and right TDBCs are easily distinguished. There is an optimal thickness of the metal film to realize the largest difference of S between Kretschmann configurations with left TDBCs and right TDBCs. Furthermore, we discuss the oscillator strength f, which is mainly determined by TDBC concentration. We find that our proposed detector is quite sensitive with f. By changing f from 0.008 to 0.014 with the step of 0.002, the change of ?S is no less than five times the incident wavelength(2.9 μm). Our proposed structure is very sensitive to the chirality and the concentration of TDBCs and has potential applications in distinguishing the chirality detector. 相似文献
The interplay of structural and electronic properties on plasmon modes was investigated for a thin Ag film grown at room temperature on Cu(111). Surface plasmons are confined within Ag grains, as indicated by the analysis of their dispersion relationship, which is dispersionless up to a critical wave-vector. Surface plasmon confinement is removed upon annealing at 400?K. The thermal treatment induces a flattening of the Ag adlayer with a merging of Ag islands, and, moreover, a strong enhancement of surface conductivity. 相似文献
This paper presents a theoretical study on a photonic crystal fiber plasmonic refractive index biosensor. The proposed photonic crystal fiber sensor introduces the concept of simultaneous detection with the linearly polarized and radially polarized modes because the sensing performance of the sensor based on both modes is relatively high, which will be useful for selecting the modes to make the detection accurately. The sharp single resonant peaks of the linearly polarized mode and radially polarized mode, are stronger and more sensitive to the variation of analyte refractive index than that of any other polarized mode in this kind of photonic crystal fiber. For linearly polarized mode and radially polarized mode, the maximum sensitivities of 10448.5nm per refractive index unit and 8230.7nm per refractive index unit can be obtained, as well as 949.8 and 791.4 for figure of merits in the sensing range of 1.33-1.45, respectively. Compared with the conventional Au-metalized surface plasmon resonance sensors, our device is better and can be applied as a biosensor. 相似文献