David Arbel

Gap plasmon polariton structure for very efficient microscale-to-nanoscale interfacing.

The seamless transition between microscale photonics and nanoscale plasmonics requires overpassing different waveguiding mechanisms and a few orders of magnitude in the lateral dimension. Exploiting gap plasmon-polariton waves both at the microscale and nanoscale with an ultrashort (few micrometers) nonadiabatic tapered gap plasmon waveguide, we show theoretically that very high-power transfer efficiency (approximately 70%) is achieved. The same mechanism may be used to harvest impinging light waves and direct them into a nanohole or slit to exhibit an anomalous transmission without the conventional periodic structures. The interplay of plasmonic and oscillating modes is analyzed.

Plasmonic modes in W-shaped metal-coated silicon grooves.

Measurements of a W-shaped metal-coated surface Plasmon polariton waveguides are presented, showing complex confined modes both in the coupled pair of air filled metal V-grooves, as well as within the central metal-coated triangular silicon wedge. Mode calculations support the experimentally measured plasmonic modes. Such W-shaped plasmonic waveguides when integrated with Metal-Oxide-Silicon structures may be utilized for active plasmonic nano-optical devices.

Light emission rate enhancement from InP MQW by plasmon nano-antenna arrays

Arrays of gold single-strip and double-strip nano-antennas, with resonance in the wavelength range of 1200-1600 nm, were fabricated on the top of InGaAs/InP multi quantum well structure. Photo-luminescence from the quantum-wells was measured and shown to be enhanced by a factor of up to 9, with maximum enhancement wavelength corresponding to the nano-antennas resonance. Emission enhancement is attributed to the coupling of emitting charge-carriers to the plasmonic nano-antennas, causing an estimated increase in the radiative recombination rate by a factor of ~25, thus making it dominant over non-radiative recombination. This effect will enable fast modulation of InP-based nano-emitters spontaneously emitting at telecom-wavelength.

Self-stabilization of dense soliton trains in a passively mode-locked ring laser

The generation of stable dense soliton trains in passively mode locked ring fiber lasers was explored theoretically. We found equilibrium states of even and odd numbers of interacting solitons in a ring configuration by employing soliton perturbation theory. In a lossless ring, these equilibrium states were unstable due to the lack of a damping mechanism both for the oscillations in the solitons parameters as well as for modulation instability. In a passively mode-locked ring fiber laser, these dense soliton trains were self-stabilized to form ordered trains. The stabilization process was initiated by the local repulsive soliton-soliton interactions and preceeded by a global soliton phase locking stemming from multimode self-injection locking. We describe in detail the evolution from a disordered to ordered dense soliton train.

Nonlinear switching and modulational instability of wave patterns in ring-shaped vertical-cavity surface-emitting lasers

We have explored theoretically and experimentally the steady-state transverse light fields emitted from ring-shaped lasers, specifically, those from vertical-cavity surface-emitting lasers (VCSELs). We saw the switching on of patterns of increasing spatial frequencies as a function of pump parameter. Furthermore, we were able to identify the mechanism for such an evolution as geometrical modulational instability within the nonlinear cavity. Other mechanisms such as the conventional gain–loss balance had no effect on the ring configuration that was modeled. The experiments with annular VCSELs gave results that matched the theoretical predictions well, although other mechanisms not considered in our model, such as carrier diffusion, took place in the experimental devices. We conclude that the nonlinear mechanisms presented here can be regarded as limiting cases in the interpretation of more-complex functions, such as patterns, modes, and filamentation switching, in VCSELs.

W-shaped Plasmon Waveguide for Silicon based Plasmonic Modulator

Measurements of W-shaped metal-coated silicon plasmon waveguide exhibit confined modes in both silicon-metal wedge and air-metal V-grooves. The highly confined mode in silicon is included in design for high efficiency fast CMOS based plasmonic modulator

Surface Plasmon Assisted Interfacing between Nano and Micro Scale Photonic Circuits

Efficient interfacing (>60% efficiency) between micro-scale waveguides and nano-scale plasmon waveguides is achieved by an ultrashort (6 microns) tapered gap plasmon waveguide. The Interplay of related plasmonic and oscillating modes is analyzed.

Plasmon nano-antenna enhanced light emission from InP MQW — Towards faster LEDs

Arrays of plasmonic nano-antennas were fabricated on InGaAs/InP multi quantum well structure. Photo-luminescence enhancement of ×9 was measured in correspondence with nano-antennas resonance, attributed to ×25 increase in radiative recombination rate.

Supermodes of Plasmonic Wedges in Structured Waveguides

In many plasmonic waveguides - modes are determined by the complex coupling of wedges within the structure. We examine systematically the mode stemming from wedge coupling and subsequently validate experimentally the generation of such modes.

High Quality 3D Virtual Nanocavity by Fringing Near-Fields of a Plasmonic Cylinder

A 50 nm diameter gold cylinder loaded on a semiconductor surface creates sub-wavelength field confinement in 3D. The virtual nano-cavity exhibits 180 nm modal volume with Q-factor of few hundreds, suitable for realizing a semiconductor based nano-laser.