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Since the electron is the photon-generator and the electron is rotating around itself and around the nucleus, the emitted photon from the electron should have the effect of these rotating motions. So, the photon has a three-dimensional motion, including a transition movement and a rotary motion. And it traverses in a helical trajectory. By using this definition, we have proved wave-particle duality at the same time and introduce a new equation for the photon motion and its energy. [ABSTRACT FROM AUTHOR]

We present a simple, high-duty-cycle, cavity-enhanced optical absorption measurement technique based on delay-limited Pound-Drever-Hall (PDH) sideband locking. The chosen circuit naturally provides realtime readout of the amplitude quadrature of the PDH error signal, which can be mapped onto the cavity's internal loss rate while using the phase quadrature to lock sideband frequency to the cavity mode. Our proofof-concept device comprises a 5-cm-long Fabry-Perot cavity with a 450 kHz bandwidth (finesse 6800, 350 ns power ringdown), and a feedback bandwidth of several MHz, limited primarily by the group delay of our electronics. This technique could readily be applied to other optical resonators such as fiber cavities, with potential applications in radiation dosimetry. [ABSTRACT FROM AUTHOR]

We study switching operation in a plasmonic coupler using fs-pulses. Simulations using the finite difference time-domain method (FDTD) are carried out showing how the output changes as the pulse energy increases raising from zero to a maximum. Both cases of neglecting and realistic losses are considered in order to compare. The work is intended to explore the use of pulses for all-optical signal processing in a potentially interesting system for integrated photonics at the nanometric scale. [ABSTRACT FROM AUTHOR]

We demonstrate a novel approach to the determination of optical loss coefficients in metal-coated fibers in a 0.4-1.9 μm wavelength range. It is based on measuring the change of temperature-dependent electrical resistance of the metal coating caused by laser radiation transmitted through the fiber. A number of single-mode and multimode metallized fibers were investigated using several laser sources operating in visible and near infrared ranges. The spectral dependencies of optical losses of copper-coated fibers were experimentally obtained. The region that corresponds to the minimum optical losses is located near 1 μm wavelength. The increase of radiation losses in 1.5-1.9 μm region is much steeper compared to polymer-coated fibers. [ABSTRACT FROM AUTHOR]

We present our investigation on the crystallization of IBS HfO2 on (0001) SiO2. The crystallization was studied by in-situ XRD. The activation energy was 2.6±0.5 eV. The growth follows a two-dimensional mode. LIDT measurements (5000-on-1) with 10 ns pulses at 355 nm on 3QWT HfO2 layers shows that the crystallization leads to increase of the laser irradiation resistance. The 0%-LIDT of the as coated sample was 3.1 J/cm2 and increased to 3.7 J/cm2 after 5h @ 500°C. [ABSTRACT FROM AUTHOR]

We demonstrate the integration of arrayed waveguide grating (AWG) de-multiplexer with a low loss and low index contrast platform, i.e., a striped-loaded slot waveguide (SLWG). The SLSW-AWG is designed to operate around the wavelength λ = 1550 nm with a four-output channel. The device experiences excellent output parameters: channel width δλ = 1.39 nm at -3dB, channel spacing Δλ = 2.43 nm and extinction ratio ER = 9.87 dB, useful for sensing applications. [ABSTRACT FROM AUTHOR]

In this work, methods and procedures are investigated for the holistic simulation of the dynamicalthermal behavior of high-performance optics like lithography objectives. Flexible multibody systems in combination with model order reduction methods, finite element thermal analysis and optical system analyses are used for transient simulations of the dynamical-thermal behavior of optical systems at low computational cost. [ABSTRACT FROM AUTHOR]

We study the impact of temporal randomness on the formation of vectorial dispersive shock-waves that emerge due to the interaction of a partially coherent probe wave co-propagating together with an orthogonally polarized intense short pulse. Experiments carried out in a normally dispersive optical fiber demonstrate that the lack of coherence of the probe landscape acts as a strong diffusive term, which is able to hamper or inhibit the vectorial shock formation. [ABSTRACT FROM AUTHOR]

We numerically study the temporal patterns that emerge upon the propagation of one or two π phase jumps in a nonlinear optical fiber. Both normal and anomalous regimes of dispersion are considered. The analytical derivation of linear patterns based on Fresnel's integrals provides some clues to better understand the properties of the resulting coherent structures. [ABSTRACT FROM AUTHOR]

We discuss the possibility of exploiting polariton-exciton physics as an analogue experimental tool to study challenging ideas and existing problems arising in the context of gravity theory and theoretical cosmology. We search for cosmology analogues with specific focus on simulating non-equilibrium dynamics across cosmological phase transitions in laboratory as well as employing optical analogue horizons in Bose-Einstein condensates (BECs) and signatures of white hole radiation to study gravitational and cosmological processes. Our analysis aims to uncover conceptual similarities between condensed matter systems and various phenomena in the Early Universe such as the symmetry breaking of the vacuum energy, spontaneous production of particles, false vacuum and cosmic inflation together with a number of unsolved cosmological problems. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate the generation of pulse trains with repetition rates of 40-GHz, 80 GHz and 200 GHz. Our approach is based on the nonlinear compression of besselon pulses in a highly-nonlinear fiber with normal dispersion. The pulses are of high quality, with a subpicosecond duration. [ABSTRACT FROM AUTHOR]

We present the concept, analysis and design of a nonreciprocal system of coupled nonlinear waveguides, operating at the near infrared. We exploit the spatial asymmetry induced by the exceptional points of a non-Hermitian coupler which, combined with saturable absorption in the nonlinear regime, can break Lorentz reciprocity. In this work, we introduce asymmetric losses in a pair of coupled silicon waveguides by overlaying only one of them with unbiased graphene, subject to saturable absorption. The device can be used as a broadband half-duplex isolator: a two-port component offering unidirectional transmission of high-power signals. [ABSTRACT FROM AUTHOR]

We report on a theoretical and experimental investigation of the optical Kerr effect in the evanescent field of silica nanofibers immersed in several highly nonlinear liquids such as ethanol, acetone and water and we further compare them with air cladding. We provide formula of the effective nonlinear coefficients including the contribution of the nanofiber silica core and of the evanescent field for varying nanofiber diameter and for different surrounding media. [ABSTRACT FROM AUTHOR]

The interaction of the adiabatically tapered photonic crystal fiber fundamental mode with a thin-film absorbing coating, deposited on a surface of a taper waist, on transmission of a tapered fiber is studied. Examples of using this interaction in refractive index sensors and for detection of an adsorption layer with ammonia molecules upon contact of the absorbing coating with a liquid medium are presented. It is obtained that a pronounced sensory effect occurs in the case of a resonant coupling between the fundamental fiber mode and cladding modes localized between photonic crystal fiber air channels and the absorbing coating. [ABSTRACT FROM AUTHOR]

We present a non-destructive and non-invasive imaging spectroscopic technique with a high spatial and spectral resolution based on the detection of the Rayleigh scattering field radiated out of a centimetric length and micrometric size optical waveguide in operation. [ABSTRACT FROM AUTHOR]

Optical micro/nanofiber, with diameter close to the wavelength of the waveguided light, leaves a considerably large fractional evanescent fields for coupling with low-dimensional functional nanostructures. Here I introduce our works on 4micro/nanofiber-coupled low-dimensional structures for nanophotonic applications including gas sensing and ultrashort pulse measurement. [ABSTRACT FROM AUTHOR]

A new all fibre, and low transmission loss, digital optical strain sensor is proposed. This sensor behaves as a Coaxial Mach-Zehnder interferometer. Special depressed cladding single-mode fibre DCF was tapered down to the micrometer scale presenting FSR in the nm range. The sensor is modelled to probe up to ± 0.2% strain when under expansive or compression stresses, returning 20 optical Power Transfer Turning Points (PTTP) at 1575 nm transmitted wavelength. [ABSTRACT FROM AUTHOR]

Ultra narrow-band absorbing surfaces answer a growing demand of precise control of absorption spectra. Starting from a design of guided mode resonator (GMR), we present here a versatile architecture presenting resonances of very high quality factors (up to 10 000) and spectrally adjustable. This design uses multiple slices of dielectrics to focus resonating field in the middle of a metallic waveguide, diminishing its extension in the metal and thus the loss rate of the propagating mode. [ABSTRACT FROM AUTHOR]

We report the design and optimized fabrication of deformed whispering gallery mode resonators in silica with solely ICP-RIE. This allows us to control the morphology of the resonators more freely and results in low surface roughness. The light was coupled into the resonator using a state of the art tapered fiber approach and we determined the Q-factor in the range of 105 [ABSTRACT FROM AUTHOR]

The high speed conversion of signals between the optical and electrical domains is crucial for many key applications of silicon photonics. Electro-optic modulators integrated with electronic drive amplifiers are typically used to convert an electrical signal to the optical domain. Design of these individual elements is important to achieve high performance, however a true optimisation requires careful co-design of the photonic and electronic components considering the properties of each other. Here we present our recent results in this area together with a MOSCAP type modulator with the potential for high speed, high efficiency and highly linear modulation. [ABSTRACT FROM AUTHOR]

We report results of laser processing of amorphous silicon and silicon-germanium semiconductor materials for the production of integrated photonic platforms. As the materials are deposited and processed at low temperatures, they are flexible, low cost, and suitable for multi-layer integration with other photonic or electronic layers. We demonstrate the formation of waveguides via crystallization of pre-patterned silicon components and functional microstructures through crystallization and compositional tuning of silicon-germanium alloy films. These results open a route for the fabrication of high density, multi-functional integrated optoelectronic chips. [ABSTRACT FROM AUTHOR]

Subwavelength structured waveguides provide tailorable optical properties that can be leveraged to overcome bandwidth limitations in a wide range of photonic devices. In this invited talk, we present an overview of recent developments on subwavelength engineered building blocks, including phase shifters, mode multiplexers, polarization beam splitters and zero-birefringence waveguides. [ABSTRACT FROM AUTHOR]