Search results for "Physics::Optics"
showing 10 items of 1958 documents
Integration of solution processed materials in polymer waveguides
2015
Active solution processed nanomaterials have emerged as a very high promising candidates for photonic applications. The reason of this arises from the facts that they exhibit high quantum yield emission at room temperature and wavelength tunability, other than their processing involves easy and cheap fabrication techniques and a versatile integration on different substrates. In this way, active properties of different solution processed materials, as colloidal quantum dots, organic dyes and rare earth nanoparticles, have been exploited to demonstrate spontaneous emission or optical modulation in photonic devices. However, in spite of such an attractiveness of these nanomaterials, little has…
Plasmonic Silver Nanorod Sensitivity: Experiment and Simple Theoretical Treatment
2013
We compare the plasmonic sensitivity of silver and gold nanorods with similar resonance wavelengths by monitoring the plasmon resonance shift of single noble metal nanorods upon changing the environment from water to sucrose solution. We find that silver nanorods have 1.2 to 2 times higher sensitivity than gold in good agreement with simulations based on the boundary-elements-method (BEM). To exclude the effect of particle volume on sensitivity, we test gold rods with increasing particle width at a given resonance wavelength. Using the Drude-model of optical properties of metal together with the quasi-static approximation (QSA) for localized surface plas-mons, we show that the dominant cont…
Near-field characterization of plasmon polariton propagation along periodically nano-structured metal thin films
2007
We operate a near-field optical microscope to investigate the properties of periodically nano-structured metal thin films designed to control at the micron scale the propagation or the excitation of surface plasmon polaritons.
All-optical and electro-optical active plasmonic telecom components
2011
Active plasmonics is an attractive emerging field in which the ability to control the surface plasmon polariton (SPP) propagation finds many applications such as realization of fully functional integrated photonic circuitry. We demonstrate both numerically and experimentally switching of the SPP transmission based on two different approaches namely the all-optical and electro-optical at telecom wavelengths. The plasmonic component consists of a compact and efficient SPP switch utilizing highly sensitive ring resonator which has high sensitivity to the refractive index changes. Fabrication was done via e-beam lithography utilizing advanced proximity corrections. The compenents were character…
Electrical excitation of surface plasmons by an individual carbon nanotube transistor.
2013
We demonstrate here the realization of an integrated, electrically driven, source of surface plasmon polaritons. Light-emitting individual single-walled carbon nanotube field effect transistors were fabricated in a plasmonic-ready platform. The devices were operated at ambient conditions to act as an electroluminescence source localized near the contacting gold electrodes. We show that photon emission from the semiconducting channel can couple to propagating surface plasmons developing in the electrical terminals. Our results show that a common functional element can be operated for two different platforms emphasizing thus the high degree of compatibility between state-of-the-art nano-optoe…
Space-time features of THz emission from optical rectification in sub-wavelength areas
2011
We present our investigation on the THz space-time emission characteristic induced by the non-paraxial generation regime in highly localized THz generation via optical rectification on sub-wavelength areas.
Spatial and spectral properties of small area THz generation for sub-wavelength microscopy
2010
A highly localized THz source is a promising candidate for sub-wavelength microscopy, due to its superior radiation power throughput with respect to others near-field techniques. Here, we report on the spatial and the spectral near-field properties of our highly localized THz source.
Ion production from solid state laser ion sources.
2010
Laser ion sources based on resonant excitation and ionization of atoms are well-established tools for selective and efficient production of radioactive ion beams. Recent developments are focused on the use of the state-of-the-art all solid-state laser systems. To date, 35 elements of the periodic table are available from laser ion sources based on tunable Ti:sapphire lasers. Recent progress in this field regarding the establishment of suitable optical excitation schemes for Ti:sapphire lasers are reported.
Photonic crystals based on two-layer opaline heterostructures
2002
AbstractOptical properties of several heterostructures representing two-layer opaline photonic crystals have been examined. Two separate stop-bands have been observed both in transmission and emission spectra. The effect of the interface disorder on the optical spectra was not observed, probably, due to the insufficient degree of order of the opaline layers.
Local Metamaterial-Based Waveguides in Gaps Between Parallel Metal Plates
2009
This letter presents a new metamaterial-based waveguide technology referred to as ridge gap waveguides. The main advantages of the ridge gap waveguides compared to hollow waveguides are that they are planar and much cheaper to manufacture, in particular at high frequencies such as for millimeter and sub- millimeter waves. The latter is due to the fact that there are no mechanical joints across which electric currents must float. The gap waveguides have lower losses than microstrip lines, and they are completely shielded by metal so no additional packaging is needed, in contrast to the severe packaging problems associated with microstrip circuits. The gap waveguides are realized in a narrow …