We study experimentally the collision of photorefractive screening solitons in a strontium barium niobate crystal. Depending on relative phase and their intersecting angle, such effects as soliton birth, energy exchange, fusion have been observed.

Weak scattering and short optical interaction lengths have, until this work, prevented the observation of trace gas Raman spectra using photonic integrated circuitry. spectroscopy is a powerful analytical tool, its implementation chip-scale waveguide devices represents critical step toward detection identification in small handheld systems. Here, we report first measurements gases nanophotonic waveguides. These were made possible highly evanescent rib waveguides functionalized with thin...

We report the measurement of waveguide-enhanced Raman spectra from trace concentrations four vapor-phase chemical warfare agent simulants: dimethyl methylphosphonate, diethyl trimethyl phosphate, and triethyl phosphate. The are obtained using highly evanescent nanophotonic silicon nitride waveguides coated with a naturally reversible hyperbranched carbosilane sorbent polymer exhibit extrapolated one-σ detection limits as low 5 ppb. use finite-element model to explain polarization wavelength...

We detect trace gases at parts-per-billion levels using evanescent-field absorption spectroscopy in silicon nitride microring resonators coated with a functionalized sorbent polymer. An analysis of the resonance line shapes enables measurement differential spectra for number vapor-phase analytes. The are obtained near-infrared overtone OH-stretch resonance, which provides information about toxicity analyte vapor.

Light sources monolithically integrated with optical filters, modulators, and detectors are necessary components for photonic systems on a chip. For broadband applications such as chemical or biological sensing using absorption spectroscopy, white light preferred over lasers amplified spontaneous emission sources. In particular, thermal offer straightforward means emission. However, to date, there have been few reports of waveguide-coupled this work, we demonstrate suspended nanophotonic...

Journal Article A Real-time, Fibre Optic Dosimetry System Using Al2O3 Fibres Get access J. C. Polf, Polf Search for other works by this author on: Oxford Academic PubMed Google Scholar S. W. McKeever, McKeever M. Akselrod, Akselrod Holmstrom Radiation Protection Dosimetry, Volume 100, Issue 1-4, 1 July 2002, Pages 301–304, https://doi.org/10.1093/oxfordjournals.rpd.a005873 Published: 01 2002

We report on the characterization of two-dimensionally confined phonon-polaritons at terahertz frequencies in suspended waveguides using Raman scattering. The cross-sectional dimensions are commensurate with wavelength phonon-polariton forward scattering leading to spectra that depend strongly physical size waveguide. use finite element numerical computations predict polariton and find excellent agreement measurements. Our observations analysis advance understanding propagation guiding...

This article describes recent research at the U.S. Naval Research Laboratory that focuses on use of micro- and nanomachining techniques for photonic waveguide devices. By selectively etching a sacrificial layer core is supported by, in whole or part, obtains enhanced properties functionality, such as mechanical flexibility, index contrast, birefringence, evanescent field depth. We describe how these enable unique applications areas cavity optomechanics, displacement sensing, electro-optics,...

Holographic polymer-dispersed liquid crystal reflective structures have been formed using a highly elastic photopolymer. The elasticity allows for mechanical tuning of the reflection notch by over 120nm in visible spectral range compressive stress. shift central position is related to strain system and an effective modulus structure obtained.

We report the design, fabrication, and measurement of waveguide lattice filters for use in integrated Raman- or fluorescence-based spectroscopy sensing systems. The consist a series broadband directional couplers optical delay sections that create an n-stage unbalanced Mach–Zehnder interferometer specifically designed to segregate pump light redshifted signal two output ports. first design criteria optimal filter performance. Then, we these with numerical beam propagation methods specific...

A two-level system is driven by two strong fields, one on resonance and close to resonance. There a resonance-like response of the coupled atom-field when detuning second field an integer fraction Rabi frequency resonant field. These subharmonic resonances are monitored transition third level give characteristic spectrum dominated series doublets.

The response of a strongly driven Rabi transition, which is associated with two-level atom, studied. Such transition exhibits Mollow splitting including gain features, and the spectrum original also altered. We demonstrate that driving produces new at its own frequency, can be to exhibit further splitting. Our experimental results are in good agreement theory based on doubly dressed states.

We report on the observation of spin echo signals at generalized Rabi frequency a strongly driven two level system. The results are obtained for radio-frequency transition nitrogen-vacancy center in diamond. A physical picture experiment is given terms dressed-state basis, and decay analyzed semiclassically found to be excellent agreement with our transient solution Bloch equations.

Highly evanescent nanophotonic waveguides enable extremely efficient Raman spectroscopy in chip-scale photonic integrated circuits due to the continuous excitation and collection of scattering along entire waveguide length. Such can be used for detection identification condensed-phase analytes, or, if functionalized by a sorbent as top-cladding, detect trace concentrations chemical species. The efficiency is modified guided-mode structures compared unconfined, micro-Raman geometries. Here,...

Under the conditions of rotating wave approximation (RWA), a transition strongly driven by resonant oscillating field displays well known symmetric Autler - Townes doublet. However, if counter-rotating component, neglected in RWA, is taken into account, Bloch Siegert shift gives rise to an doublet unequal intensity even case driving field. This effect investigated theoretically V-shaped three-level double-resonance configuration and results are presented this paper. An interesting...

Sorbent materials are utilized in a range of analytical applications including coatings for preconcentrator devices, chromatography stationary phases, and as thin film transducer used to concentrate analyte molecules interest detection. In this work we emphasize the use sorbent target absorption vapors examine their molecular interaction with by optically probing it infrared (IR) light. The complex spectral changes which may occur during binding specific sites can significantly aid custom...

The spatial distribution of the power transfer achieved by contradirectional two-beam coupling using self-pumped photorefractive reflection gratings is investigated in two materials with different gain coefficients, LiNbO3:Fe and KNbO3:Fe. Incremental portions volume grating are erased optically inducing thin optical damage planes, reducing overall efficiency. By monitoring effect local disruption, spatially resolved throughout crystal, results found to be agreement our theoretical predictions.

The vapor-phase Raman spectra of trace concentrations chemicals are measured using highly evanescent silicon nitride rib waveguides functionalized with a top cladding that is designed to strongly sorb organophosphonates and other toxic species.