We propose a passive polarization depolarizer to overcome the polarization noise in Brillouin optical time domain reflectometry (BOTDR). We also give a theoretical analysis of the depolarizer. The depolarizer is highly stable and has small insertion loss. It is based on a Mach-Zehnder interference scheme and mainly consists of two ...

In response to the incident light's electric field, the electron density oscillates in the plasmonic hotspots producing an electric current. Associated Ohmic losses raise the temperature of the material within the plasmonic hotspot above the melting point. A nanojet and nonosphere ejection can then be observed precisely from the plasmonic ...

Because of stronger optical confinement density, silicon slot waveguides tend to have higher scattering loss than normal ridge waveguides with same sidewall roughness. A wet chemical process is found to be highly effective in reducing the surface roughness and scattering loss. A reduction in scattering loss by 10.2 dB/cm for ...

We study light propagation in a photonic system that shows stepwise evolution in a discretized environment. It resembles a discrete-time version of photonic waveguide arrays or quantum walks. By introducing controlled photon losses to our experimental setup, we observe unexpected effects like subexponential energy decay and formation of complex fractal ...

We fabricated waveguides in Pr:SrAl₁₂O₁₉ crystals by direct femtosecond laser writing. The propagation losses were calculated to be as low as 0.16 dB/cm at a wavelength of 633 nm. Laser oscillation in a diode-pumped waveguide at a wavelength of 643.5 nm was realized. The output power of the waveguide laser was 28.1 mW at ...

We report on the detection of picosecond pulsed squeezed light generated by an optical parametric amplification in a periodically poled MgO:LiNbO₃ waveguide. By using a temporally shaped local oscillator in a balanced homodyne detection, we obverved the squeezing of -5.0 dB below the shot noise level. The squeezing level at the ...

Vibratory measurements of the structures of the ear are key to understanding much of the pathology in mouse models of hearing loss. Unfortunately the high-speed sampling required to interrogate the high end of the mouse hearing spectrum is beyond the reach of most optical coherence tomography (OCT) systems. To address ...

The design and construction of a circular microphone array (CMA) that has a wide frequency range suitable for human hearing is presented. The design of the CMA was achieved using a technique based on simulated directivity index (DI) curves. The simulated DI curves encapsulate the critical microphone array performance limitations: ...

Optical waveguides were fabricated in neodymium-doped silicate glass by using a low-repetition-rate (1 kHz) femtosecond laser inscription. Two different types of waveguide structure are fabricated. In the first, guiding occurs in the focal spot. In the second, guiding occurs in the region between the two filaments. The near-field intensity distribution, ...

We demonstrate a widely tunable L-band multiwavelength Brillouin-erbium fiber laser utilizing a nonlinear amplified fiber loop mirror filter (AFLMF). By manipulating polarization controllers placed in the fiber loop, the erbium peak gain spectrum is able to be shifted. The nonlinear AFLMF induces wavelength-dependent cavity loss and serves as an amplitude ...

We show that dispersion-enhanced phase noise (DEPN) induces performance degradations in both conventional CO-OFDM systems and reduced-guard-interval (RGI) CO-OFDM systems employing RF-pilot phase compensation. After analytically studying DEPN, we show that DEPN causes a 2 to 6 dB optical signal-to-noise ratio (OSNR) penalty at transmission distances of 3200 km and ...

We demonstrate a wafer-bonded silica-on-silicon planar waveguide platform with record low total propagation loss of (0.045 ± 0.04) dB/m near the free space wavelength of 1580 nm. Using coherent optical frequency domain reflectometry, we characterize the group index, fiber-to-chip coupling loss, critical bend radius, and propagation loss of these waveguides.

We design and demonstrate a birefringent Michelson interferometer based interleaver with ultra-low dispersion and low cost. The interleaver consists of polarizing beam splitters (PBS's) and quarter-wave plates and half-wave plates. The PBS's based Michelson interferometers provide the optical path difference for interference between the two orthogonal polarization components and the ...

A pulsed mid-infrared pump at λ=2173 nm is used to demonstrate wideband optical parametric gain in a low-loss 2 cm long silicon photonic wire. Using dispersion engineering to obtain negative second-order (β₂) and positive fourth-order (β₄) dispersion, we generate broadband modulation instability and parametric fluorescence extending from 1911 nm-2486 nm. Using a cw probe ...

A low-loss, compact, and highly sensitive optical fiber curvature sensor is presented. The device consists of two identical low-loss fused fiber tapers in tandem separated by a distance L. When the optical fiber is kept straight and fixed, no interference pattern appears in the transmitted spectrum. However, when the device ...

In this study, a three-dimensional finite-element model of the passive human cochlea was created. Dynamic behavior of the basilar membrane caused by the vibration of the stapes footplate was analyzed considering a fluid-structure interaction with the cochlear fluid. Next, the effects of a perilymphatic fistula (PLF) on the vibration of ...

High-efficiency ultra-broadband wavelength converters based on double-pass quasi-phase-matched cascaded sum and difference frequency generation including engineered chirped gratings in lossy lithium niobate waveguides are numerically investigated and compared to the single-pass counterparts, assuming a large twin-pump wavelength difference of 75 nm. Instead of uniform gratings, few-section chirped gratings with the ...

We report on a bendable photonic crystal fiber for short pulse high power fiber laser applications. This fiber uses a double lattice structure and enables single mode operation with a very large mode area that reaches 1454 µm² when the fiber is kept straight and 655 µm² in the fiber ...

We report the design and characterization of Si₃N₄/SiO₂ optical waveguides which are specifically developed for optical delay lines in microwave photonics (MWP) signal processing applications. The waveguide structure consists of a stack of two Si₃N₄ stripes and SiO₂ as an intermediate layer. Characterization of the waveguide propagation loss was performed ...

We report on the realization of long-range dielectric-loaded surface plasmon polariton waveguides (LR-DLSPPWs) consisting of straight and bent subwavelength dielectric ridges deposited on thin and narrow metal stripes supported by a dielectric buffer layer covering a low-index substrate. Using imaging with a near-field optical microscope and end-fire coupling with a ...

We propose and demonstrate an integrated optical isolator in InP using two phase modulators in series. The phase modulators are driven with a single-frequency signal in quadrature. Theoretically there is no effect on the forward signal, and the carrier of the backward signal can be eliminated, the energy distributed to ...

We find the conditions upon the amplitude and frequency of an external electromagnetic field at which the dipole moment of a Bergman-Stockman spaser oscillates in antiphase with the field. For these values of the amplitude and frequency the loss in metal nanoparticles is exactly compensated by the gain. This shows ...

The objective of this research was to investigate the possibility of compensating for the insertion losses of the wavelet inverse-transform processors using SAW devices. The motivation for this work was prompted by the processors which are of large insertion losses. In this paper, the insertion losses are the key problem ...

An ultralow coupling loss and broad bandwidth fiber-to-waveguide mode-size converter is demonstrated for nano-scale waveguides on SOI platform using CMOS technology in this paper. The mode-size converter consists of a cantilevered PECVD SiO₂ waveguide and a-Si nano-tapers by removing the adjacent SiO₂ layer and underlying substrate Si. The a-Si waveguide ...

Plasmonic mode-size converters (PMSCs) for long-range surface plasmon polaritons (LR-SPPs) at the wavelength of 1.55 μm are presented. The PMSC is composed of an insulator-metal-insulator waveguide (IMI-W), a laterally tapered insulator-metal-insulator-metal-insulator waveguide (LT-IMIMI-W), and an IMIMI-W in series. The mode-intensity sizes of the LR-SPPs for the IMI-W and the IMIMI-W ...

We report the heterodyne detection and phase locking of a 2.5 THz quantum cascade laser (QCL) using a terahertz frequency comb generated in a GaAs photomixer using a femtosecond fiber laser. With 10 mW emitted by the QCL, the phase-locked signal at the intermediate frequency yields 80 dB of signal-to-noise ratio in a ...

We study the spectral properties of polarization-dependent loss (PDL) in fiber routes with multiple spans and amplifiers. In these systems, PDL stems from a small number of lumped WDM components interconnected by PDL-free fibers, a configuration that is poorly described by the popular model of distributed PDL. We derive transparent ...

We propose a type of lossless nonlinear polarizer, novel to our knowledge, a device that transforms any input state of polarization (SOP) of a signal beam into one and the same well-defined SOP toward the output, and perform this without any polarization-dependent losses. At the polarizer output end, the signal ...

We propose a novel embedded-core hollow optical fiber composed of a central air hole, a semi-elliptical core, and an annular cladding. The fiber characteristics are investigated based on the finite element method (FEM), including mode properties, birefringence, confinement loss, evanescent field and bending loss. The results reveal that the embedded-core ...

A tunable fiber ring laser based on an in-line two-taper Mach-Zehnder interferometer (MZI) filter was realized, and the effect of beam waists of the tapers on performance of the laser was investigated with different beam waists of 70 μm, 49 μm, and 33 μm. Experimental results show that the tunable laser with MZI ...

We show that optical signal propagation in a coupled resonator optical waveguide (CROW) does not introduce additional performance penalties with respect to propagation in a conventional optical waveguide. The result is demonstrated in a low-loss (1 dB) eight-ring silicon CROW by means of bit error rate measurements performed over the whole ...

We present thermal mass loss calculations over evolutionary time scales for the investigation if the smallest transiting rocky exoplanets CoRoT-7b (∼1.68REarth) and Kepler-10b (∼1.416REarth) could be remnants of an initially more massive hydrogen-rich gas giant or a hot Neptune-class exoplanet. We apply a thermal mass loss formula which yields results ...

We describe time domain characterizations of dynamic four-wave mixing in a low loss modified W1 GaInP photonic crystal waveguide. Using 32 ps wide pump pulses with peak powers of up to 1.1 W we achieved a very large conversion efficiency of -6.8 dB as well as a 1.3 dB parametric gain experienced by a ...

Waveguiding structures are one of the fundamental components of integrated photonic circuitry. Devices with low loss and a linear response across a wide wavelength range are especially desirable. In the present Letter, we have successfully developed and characterized low-loss silica waveguides integrated on a silicon substrate with a novel suspended ...

Properties of shear horizontal acoustic plate modes (SHAPMs) in BT-cut quartz were calculated and measured. A delay line with a long interdigital transducer, deposited on ¿50.5°YX90°-oriented quartz plate, was used for the measurements. For one of the SHAPMs, at a frequency of about 100.4 MHz, insertion loss, turnover temperature, and ...

This paper presents a simple method for fabricating SU8 three dimensional (3D) prisms with very small inclined-angles for optical-fiber/planar-waveguide interconnection with low insertion-loss by combining self-filling, molding and nano-lithography processes on plane surface. The prisms possess ultra low 3D inclined angle of 0.6° and a small surface roughness of 3.5 ...

A compact, low-noise, single-frequency fiber laser by using a newly developed Yb³⁺ heavily doped single-mode phosphate glass fiber has been demonstrated. Over 400 mW stable continuous wave single transverse and longitudinal mode laser at 1.06 μm was achieved from a 0.8 cm long active fiber. The measured slope efficiency and estimated quantum efficiency ...

We present a theory of the effective dielectric response of metamaterials containing gain. We demonstrate analytically that the conditions of spaser generation and the full loss compensation in a dense resonant plasmonic-gain metamaterial are identical. Consequently, attempting the full compensation or overcompensation of losses by gain will lead to an ...

We demonstrate single mode terahertz (THz) guidance in hollow-core kagome microstructured fibers over a broad frequency bandwidth. The fibers are characterized using a THz time-domain spectroscopy (THz-TDS) setup, incorporating specially designed THz lenses to achieve good mode overlap with the fundamental mode field distribution. Losses 20 times lower than the ...

We show that in high-index-contrast nanoscale waveguides counter propagating waves can posses distinct spatial near-field profiles. Using transmission-based near-field scanning optical microscopy (TraNSOM), we identify and map the unique near-field intensity distributions of these counter-propagating modes in a single-mode silicon waveguide. Based on this phenomenon, we design and simulate an ...

Compared with an optical modulator based on lithium niobate, the total loss of the current high speed silicon modulator is still too high for commercial use. Reduction of the total loss always comes along with the degradation of the other two characteristics including modulation efficiency or switching speed. In this ...

Modal properties of vertical cavity surface-emitting lasers (VCSELs) with holey structures are studied using a finite difference time domain (FDTD) method. We investigate loss behavior with respect to the variation of structural parameters, and explain the loss mechanism of VCSELs. We also propose an effective method to estimate the modal ...

We investigate numerically the formation of extreme events or rogue waves in soft glass tellurite fibers and demonstrate that optical loss drastically diminishes shot-to-shot fluctuations characteristic of picosecond pumped supercontinuum (SC). When loss is neglected these fluctuations include extreme events such as formation of highly energetic pulses located at the ...

Magnetic resonance elastography (MRE) is used to quantify the viscoelastic shear modulus, G*, of human and animal tissues. Previously, values of G* determined by MRE have been compared to values from mechanical tests performed at lower frequencies. In this study, a novel dynamic shear test (DST) was used to measure ...

In a system of non-linear chemical reactions called the Brusselator, we show that intrinsic noise can be regulated to drive it to exhibit resonance in the presence of a sub-threshold signal. The phenomena of periodic stochastic resonance and aperiodic stochastic resonance, hitherto studied mostly with extrinsic noise, is demonstrated here ...

In active sonar the target echo level is often estimated with a propagation model that adds all multipath arrivals. If the (post-correlator) transmitted pulse is short compared to the multipath time spread then there is effectively an extra loss (which may be substantial) since only a few of the paths ...

We demonstrate and describe how nanoporous liquid core waveguides can exclude scattering particles, making them an ideal integrated platform for analysis of turbid solutions. Milk with 0.5% fat showed an optical propagation loss of 0.05 dB/mm at 633 nm in nanoporous waveguides compared to the 10.6 dB/mm loss in standard cuvette measurements. To ...

Low-loss electromagnetic composites with high permittivity and permeability will benefit the miniaturization and multifunctional of RF devices. A kind of low-loss dielectric-magnetic ceramic-ceramic composite was developed by hybrid processing technology with the goal of integrating the dielectric properties and magnetic properties. The hybrid processing technology exhibits the advantage of lowered ...

We experimentally show vertically stacked, multi-layer, low-temperature deposited photonics for integration on processed microelectronics. Waveguides, microrings, and crossings are fabricated out of 400°C PECVD Si₃N₄ and SiO₂ in a two layer configuration. Waveguide losses of ~1 dB/cm in the L-band are demonstrated using standard processing and without post-deposition annealing, along ...

We simulate and analyze the propagation of truncated temporal Airy pulses in a single mode fiber in the presence of self-phase modulation and anomalous dispersion as a function of the launched Airy power and truncation coefficient. Soliton pulse shedding is observed, where the emergent soliton parameters depend on the launched ...