5,634 research outputs found
Low-power optical beam steering by microelectromechanical waveguide gratings
Optical beam steering is key for optical communications, laser mapping
(LIDAR), and medical imaging. For these applications, integrated photonics is
an enabling technology that can provide miniaturized, lighter, lower cost, and
more power efficient systems. However, common integrated photonic devices are
too power demanding. Here, we experimentally demonstrate, for the first time,
beam steering by microelectromechanical (MEMS) actuation of a suspended silicon
photonic waveguide grating. Our device shows up to 5.6{\deg} beam steering with
20 V actuation and a power consumption below the W level, i.e. more than 5
orders of magnitude lower power consumption than previous thermo-optic tuning
methods. The novel combination of MEMS with integrated photonics presented in
this work lays ground for the next generation of power-efficient optical beam
steering systems
The role of index contrast in the efficiency of absoprtion and emission of a luminescent particle near a slab waveguide
Enhancement of raman scattering efficiency by a metallic nano-antenna on top of a high index contrast waveguide
We theoretically study coupling of dipole radiation into integrated Si3N4 strip waveguides functionalized with a nanoplasmonic antenna. This structure enables efficient coupling of enhanced Raman signals into the fundamental TE-mode of the waveguide
On the performance of tantalum pentoxide and silicon nitride slot waveguides for on-chip raman spectroscopy
Enhanced spontaneous raman signal collected evanescently by silicon nitride slot waveguides
We investigate the effect of waveguide geometry on the conversion efficiency of Raman signals collected by integrated photonic waveguides. Compared to strip-type photonic wires, we report a six-fold increase in conversion efficiency for silicon-nitride slot-waveguides
Surface enhanced Raman spectroscopy using a single mode nanophotonic-plasmonic platform
Surface Enhanced Raman Spectroscopy (SERS) is a well-established technique
for enhancing Raman signals. Recently photonic integrated circuits have been
used, as an alternative to microscopy based excitation and collection, to probe
SERS signals from external metallic nanoparticles. However, in order to develop
quantitative on-chip SERS sensors, integration of dedicated nanoplasmonic
antennas and waveguides is desirable. Here we bridge this gap by demonstrating
for the first time the generation of SERS signals from integrated bowtie
nanoantennas, excited and collected by a single mode waveguide, and rigorously
quantify the enhancement process. The guided Raman power generated by a
4-Nitrothiophenol coated bowtie antenna shows an 8 x 10^6 enhancement compared
to the free-space Raman scattering. An excellent correspondence is obtained
between the theoretically predicted and observed absolute Raman power. This
work paves the way towards fully integrated lab-on-a-chip systems where the
single mode SERS-probe can be combined with other photonic, fluidic or
biological functionalities.Comment: Submitted to Nature Photonic
Surface enhanced Raman spectroscopy on single mode nanophotonic-plasmonic waveguides
We analyze the generation of Surface Enhanced Raman Spectroscopy signals from integrated bowtie antennas, excited and collected by a single mode silicon nitride waveguide, and discuss strategies to enhance the Signal-to-Noise Ratio
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