50 research outputs found
A quantum photonics model for non-classical light generation using integrated nanoplasmonic cavity-emitter systems
The implementation of non-classical light sources is becoming increasingly
important for various quantum applications. A particularly interesting approach
is to integrate such functionalities on a single chip as this could pave the
way towards fully scalable quantum photonic devices. Several approaches using
dielectric systems have been investigated in the past. However, it is still not
understood how on-chip nanoplasmonic antennas, interacting with a single
quantum emitter, affect the quantum statistics of photons reflected or
transmitted in the guided mode of a waveguide. Here we investigate a quantum
photonic platform consisting of an evanescently coupled nanoplasmonic
cavity-emitter system and discuss the requirements for non-classical light
generation. We develop an analytical model that incorporates quenching due to
the nanoplasmonic cavity to predict the quantum statistics of the transmitted
and reflected guided waveguide light under weak coherent pumping. The
analytical predictions match numerical simulations based on a master equation
approach. It is moreover shown that for resonant excitation the degree of
anti-bunching in transmission is maximized for an optimal cavity modal volume
and cavity-emitter distance . In reflection, perfectly anti-bunched
light can only be obtained for specific combinations. Finally, our
model also applies to dielectric cavities and as such can guide future efforts
in the design and development of on-chip non-classical light sources using
dielectric and nanoplasmonic cavity-emitter systems
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
Integration of Single Photon Emitters in 2D Layered Materials with a Silicon Nitride Photonic Chip
Photonic integrated circuits (PICs) enable miniaturization of optical quantum
circuits because several optic and electronic functionalities can be added on
the same chip. Single photon emitters (SPEs) are central building blocks for
such quantum circuits and several approaches have been developed to interface
PICs with a host material containing SPEs. SPEs embedded in 2D transition metal
dichalcogenides have unique properties that make them particularly appealing as
PIC-integrated SPEs. They can be easily interfaced with PICs and stacked
together to create complex heterostructures. Since the emitters are embedded in
a monolayer there is no total internal reflection, enabling very high light
extraction efficiencies without the need of any additional processing to allow
efficient single photon transfer between the host and the underlying PIC.
Arrays of 2D-based SPEs can moreover be fabricated deterministically through
STEM patterning or strain engineering. Finally, 2D materials grown with high
wafer-scale uniformity are becoming more readily available, such that they can
be matched at the wafer level with underlying PICs. Here we report on the
integration of a WSe monolayer onto a Silicon Nitride (SiN) chip. We
demonstrate the coupling of SPEs with the guided mode of a SiN waveguide and
study how the on-chip single photon extraction can be maximized by interfacing
the 2D-SPE with an integrated dielectric cavity. Our approach allows the use of
optimized PIC platforms without the need for additional processing in the host
material. In combination with improved wafer-scale CVD growth of 2D materials,
this approach provides a promising route towards scalable quantum photonic
chips
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
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
On-chip enhanced raman spectroscopy using metal slot waveguide
info:eu-repo/semantics/publishe
Nanophotonic waveguide enhanced Raman spectroscopy of biological submonolayers
Characterizing a monolayer of biological molecules has been a major
challenge. We demonstrate nanophotonic wave-guide enhanced Raman spectroscopy
(NWERS) of monolayers in the near-infrared region, enabling real-time
measurements of the hybridization of DNA strands and the density of
sub-monolayers of biotin-streptavidin complex immobilized on top of a photonics
chip. NWERS is based on enhanced evanescent excitation and collection of
spontaneous Raman scattering near nanophotonic waveguides, which for a one
centimeter silicon nitride waveguide delivers a signal that is more than four
orders of magnitude higher in comparison to a confocal Raman microscope. The
reduced acquisition time and specificity of the signal allows for a
quantitative and real-time characterization of surface species, hitherto not
possible using Raman spectroscopy. NWERS provides a direct analytic tool for
monolayer research and also opens a route to compact microscope-less
lab-on-a-chip devices with integrated sources, spectrometers and detectors
fabricated using a mass-producible CMOS technology platform