Nonlinear photon-assisted tunneling transport in optical gap antennas.
International audience; We introduce strongly coupled optical gap antennas to interface optical radiation with current-carrying electrons at the nanoscale. The transducer relies on the nonlinear optical and electrical properties of an optical gap antenna operating in the tunneling regime. We discuss the underlying physical mechanisms controlling the conversion involving d-band electrons and demonstrate that a simple two-wire optical antenna can provide advanced optoelectronic functionalities beyond tailoring the electromagnetic response of a single emitter. Interfacing an electronic command layer with a nanoscale optical device may thus be facilitated by the optical rectennas discussed here.
Mapping surface plasmon propagation by collection-mode near-field microscopy
Surface plasmon propagation along striped Gold structures has been investigated by collection-mode near-field microscopy, leading to map the field intensity at the structure surface and to assess the system behavior at the nanoscale.
In-plane remote photoluminescence excitation of carbon nanotube by propagating surface plasmon
International audience; In this work, we demonstrate propagating surface plasmon polariton (SPP) coupled photoluminescence (PL) excitation of single-walled carbon nanotube (SWNT). SPPs were launched at a few micrometers from individually marked SWNT, and plasmon-coupled PL was recorded to determine the efficiency of this remote in-plane addressing scheme. The efficiency depends upon the following factors: (i) longitudinal and transverse distances between the SPP launching site and the location of the SWNT and (ii) orientation of the SWNT with respect to the plasmon propagation wave vector (k(SPP)). Our experiment explores the possible integration of carbon nanotubes as a plasmon sensor in p…
Determinant role of the edges in defining surface plasmon propagation in stripe waveguides and tapered concentrators
International audience; In this paper, we experimentally show the effect of waveguide discontinuity on the propagation of the surface plasmon in metal stripes and tapered terminations. Dual-plane leakage microscopy and near-field microscopy were performed on Au stripes with varied widths to imag29e the surface plasmon intensity distribution in real and reciprocal spaces. We unambiguously demonstrate that edge diffraction is the limiting process determining the cutoff conditions of the surface plasmon mode. Finally, we determine the optimal tapered geometry leading to the highest transmission.
Electron-induced limitation of surface plasmon propagation in silver nanowires
Plasmonic circuitry is considered as a promising solution-effective technology for miniaturizing and integrating the next generation of optical nano-devices. A key element is the shared metal network between electrical and optical information enabling an efficient hetero-integration of an electronic control layer and a plasmonic data link. Here, we investigate to what extend surface plasmons and current-carrying electrons interfere in such a shared circuitry. By synchronously recording surface plasmon propagation and electrical output characteristics of single chemically-synthesized silver nanowires we determine the limiting factors hindering the co-propagation of electrical current and sur…
Contrôle de nano-antennes optiques par une commande électrique : tuner plasmonique et transduction
Optical nano-antennae are the new class of components to control light/matterinteraction at the nanoscale. These devices are operating in the visible to near infraredpart of the spectrum. The properties of these nano objects are controlled by theform, the size and the material.In the radio frequency domain, the tuner changes dynamically the operatingwavelength of the antenna. In this thesis work, we search to transfer this conceptto the nanoscale. The principle is to change the load impedance of the antenna, i.e.changing the optical index of the dielectric medium around the nano-object. Forthat we used anisotropic liquid cristal molecules. The value of the optical index iscontrolled by appl…
Launching propagating surface plasmon polaritons by a single carbon nanotube dipolar emitter.
International audience; We report on the excitation of propagating surface plasmon polaritons in thin metal films by a single emitter. Upon excitation in the visible regime, individual semiconducting single-walled carbon nanotubes are shown to act as directional near-infrared point dipole sources launching propagating surface plasmons mainly along the direction of the nanotube axis. Plasmon excitation and propagation is monitored in Fourier and real space by leakage radiation microscopy and is modeled by rigorous theoretical calculations. Coupling to plasmons almost completely reshapes the emission of nanotubes both spatially and with respect to polarization as compared to photoluminescence…
Tuning of an Optical Dimer Nanoantenna by Electrically Controlling Its Load Impedance
International audience; Optical antennas are elementary units used to direct optical radiation to the nanoscale. Here we demonstrate an active control over individual antenna performances by an external electrical trigger. We find that by an in-plane command of an anisotropic load medium, the electromagnetic interaction between individual elements constituting an optical antenna can be controlled, resulting in a strong polarization and tuning response. An active command of the antenna is a prerequisite for directing light wave through the utilization of such a device.
Spontaneous hot-electron light emission from electron-fed optical antennas
Nanoscale electronics and photonics are among the most promising research areas providing functional nano-components for data transfer and signal processing. By adopting metal-based optical antennas as a disruptive technological vehicle, we demonstrate that these two device-generating technologies can be interfaced to create an electronically-driven self-emitting unit. This nanoscale plasmonic transmitter operates by injecting electrons in a contacted tunneling antenna feedgap. Under certain operating conditions, we show that the antenna enters a highly nonlinear regime in which the energy of the emitted photons exceeds the quantum limit imposed by the applied bias. We propose a model based…
Silencing and enhancement of second-harmonic generation in optical gap antennas
International audience; Amplifying local electromagnetic fields by engineering optical interactions between individual constituents of an optical antenna is considered fundamental for efficient nonlinear wavelength conversion in nanometer-scale devices. In contrast to this general statement we show that high field enhancement does not necessarily lead to an optimized nonlinear activity. In particular, we demonstrate that second-harmonic responses generated at strongly interacting optical gap antennas can be significantly suppressed. Numerical simulations are confirming silencing of second-harmonic in these coupled systems despite the existence of local field amplification. We then propose a…
Excitation of a one-dimensional evanescent wave by conical edge diffraction of surface plasmon
International audience; The experimental observation of a one-dimensional evanescent wave supported by a 90◦ metal edge is reported. Through a measurement of in-plane momenta, we clearly demonstrate the dimensional character of this surface wave and show that it is non-radiative in the superstrate. Excitation conditions, lateral extension and polarization properties of this wave are discussed. Finally, we explore the effect of the surrounding dielectric medium and demonstrate that a single edge can sustain distinct excitations.
Electrical excitation of surface plasmons by an individual carbon nanotube transistor.
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…