40,135 results match your criteria Optics Express [Journal]


Coherent-hybrid STED: high contrast sub-diffraction imaging using a bi-vortex depletion beam.

Opt Express 2019 Mar 5;27(6):8092-8111. Epub 2019 Mar 5.

i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal.

Stimulated emission depletion (STED) fluorescence microscopy squeezes an excited spot well below the wavelength scale using a doughnut-shaped depletion beam. To generate a doughnut, a scale-free vortex phase modulation (2D-STED) is often used because it provides maximal transverse confinement and radial-aberration immunity (RAI) to the central dip. However, RAI also means blindness to a defocus term, making the axial origin of fluorescence photons uncertain within the wavelength scale provided by the confocal detection pinhole. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.008092DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6420153PMC

Scanning wavefront folding interferometers.

Opt Express 2019 Mar;27(5):7738-7750

We present modified scanning-type wavefront folding interferometers (WFIs), which allow spatial coherence measurements of non-uniformly correlated fields, where the degree of coherence is a function of two absolute spatial coordinates instead of coordinate separation only (Schell model). As an alternative to conventional prism-based WFI implementations, we introduce a scheme based on reflections by three mirrors. This setup allows us to avoid obstructions due to prism corners, and it is remarkably robust to polarization effects. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007738DOI Listing

Memory-controlled deep LSTM neural network post-equalizer used in high-speed PAM VLC system.

Opt Express 2019 Mar;27(5):7822-7833

Linear and nonlinear impairments severely limit the transmission performance of high-speed visible light communication systems. Neural network-based equalizers have been applied to optical communication systems, which enables significantly improved system performance, such as transmission data rate and distance. In this paper, a memory-controlled deep long short-term memory (LSTM) neural network post-equalizer is proposed to mitigate both linear and nonlinear impairments in pulse amplitude modulation (PAM) based visible light communication (VLC) systems. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007822DOI Listing

Aberration-resistible topological charge determination of annular-shaped optical vortex beams using Shack-Hartmann wavefront sensor.

Opt Express 2019 Mar;27(5):7803-7821

Determining topological charge (TC) of optical vortex (OV) beams is important for many applications, such as optical measurement and information transmission through long-distance propagation. In this application, the OV beams usually have an annular intensity profile at the receiving end and are inevitably distorted by aberrations during propagation. In this paper, we propose a simple, direct, and aberration-resistible method to determine the TC value of this annular-shaped OV beam with a Shack-Hartmann wavefront sensor (SH-WFS). Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007803DOI Listing

Three-dimensional focal stack imaging in scanning transmission X-ray microscopy with an improved reconstruction algorithm.

Opt Express 2019 Mar;27(5):7787-7802

Focal stack (FS) is an effective technique for fast 3D imaging in high-resolution scanning transmission X-ray microscopy. Its crucial issue is to assign each object within the sample to the correct position along the optical axis according to a proper focus measure. There is probably information loss with previous algorithms for FS reconstruction because the old algorithms can only detect one focused object along each optical-axial pixel line (OAPL). Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007787DOI Listing
March 2019
1 Read

Optical anisotropy of non-perturbative high-order harmonic generation in gapless graphene.

Opt Express 2019 Mar;27(5):7776-7786

High harmonic generation in atomic or molecular targets stands as a robust mechanism to produce coherent ultrashort pulses with controllable polarization in the extreme-ultraviolet. However, the production of elliptically or circularly-polarized harmonics is not straightforward, demanding complex combinations of elliptically or circularly-polarized drivers, or the use of molecular alignment techniques. Nevertheless, recent studies show the feasibility of high-harmonic generation in solids. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007776DOI Listing
March 2019
3 Reads

Numerical investigation of imaging-free terahertz generation setup using segmented tilted-pulse-front excitation.

Opt Express 2019 Mar;27(5):7762-7775

Recently a hybrid-type terahertz (THz) pulse source was proposed for high energy terahertz pulse generation. It is the combination of the conventional tilted-pulse-front setup and a nonlinear crystal with a transmission stair-step echelon of period in the hundred-micrometer range etched into the front face. The tilt angle introduced by the conventional tilted-pulse-front setup (pre-tilt) was chosen to be equal to the tilt-angle needed inside the nonlinear crystal (62° for lithium niobate (LN)) in order to fulfill velocity-matching. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=oe-27-5-7762
Publisher Site
http://dx.doi.org/10.1364/OE.27.007762DOI Listing
March 2019
4 Reads

Enhanced terahertz radiation by an intense femtosecond laser field assisted with sub-cycle pulses.

Opt Express 2019 Mar;27(5):7751-7761

In this work, we theoretically investigate the enhanced Terahertz (THz) radiation by an intense laser pulse assisted with sub-cycle pulses (SCP) in the framework of quantum theory. By numerically solving the Schrödinger equation, the production and the dynamics of ionized electrons are analyzed. The simulations show that the SCP plays different roles for different time delays in the generation of THz radiation, such as increasing the production of the ionized electrons and manipulating their trajectories. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007751DOI Listing
March 2019
1 Read

Super-resolution imaging for infrared micro-scanning optical system.

Opt Express 2019 Mar;27(5):7719-7737

The image super-resolution (SR) reconstruction technology based on the micro-scanning system is one of the best methods for realizing high-resolution infrared imaging. Thus, in this work, we first present a frequency domain phase-based projection onto convex sets SR reconstruction algorithm. This method takes advantage of the texture details and contrast-independent feature of the phase information in the frequency domain and can be used to realize image denoising and SR reconstruction for the infrared image simultaneously. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007719DOI Listing

High quality factor electromagnetically induced transparency-like effect in coupled guided-mode resonant systems.

Opt Express 2019 Mar;27(5):7712-7718

We numerically study a dielectric coupled guided-mode resonant (GMR) system, which includes two silicon (Si) grating waveguide layers (GWLs) stacked on CaF substrates. It is confirmed that the coupling between the top and bottom GMR modes starts once a Fabry-Perot (F-P) resonator is introduced, and electromagnetically induced transparency (EIT)-like spectral responses occur in the coupled GMR systems. A very narrow transparency window with a high-quality (Q) factor EIT-like effect of up to 288,892 was demonstrated. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007712DOI Listing

Quantitative assessment of nonlinearly absorbed energy in fused silica via time-resolved digital holography.

Opt Express 2019 Mar;27(5):7699-7711

A fraction of incident optical energy nonlinearly absorbed by a solid medium is considered to be the main quantitative parameter of damage-inducing light-matter interaction. However, its reliable experimental evaluation is a non-trivial task. We have addressed this problem using time-resolved digital holography. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007699DOI Listing
March 2019
1 Read

Nuisance alarm reduction: Using a correlation based algorithm above differential signals in direct detected phase-OTDR systems.

Opt Express 2019 Mar;27(5):7685-7698

Significant research efforts have focused on techniques for alleviating the nuisance alarm rate (NAR) in the field of ϕ-OTDR pattern recognition systems. Unfortunately, ephemeral events were mostly neglected in previous research and algorithms meant for improving classification accuracy were emphasized at the cost of acquiring a very large number of traces. This problem engendered an additional source of NAR in a specific class of events. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007685DOI Listing

Omnidirectional polarization beam splitter for white light.

Opt Express 2019 Mar;27(5):7673-7684

As a key element in optical systems, a broadband and omnidirectional polarization beam splitter has been long desired. Here, based on anisotropic metamaterials, a perfect polarizing beam splitter is theoretically designed for the extremely broad frequency and angle bands without energy loss. When an electromagnetic wave is incident on the beam splitter, the transverse magnetic-polarized component suffers total reflection, while the transverse electric-polarized component is completely transmitted within the incident angle range [-90°, 90°] for the white light. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007673DOI Listing

Oceanic spectrum of unstable stratification turbulence with outer scale and scintillation index of Gaussian-beam wave.

Opt Express 2019 Mar;27(5):7656-7672

We develop a new spectrum of the refractive-index fluctuations for the unstable stratification ocean based on the linear combination of the temperature spectrum, salinity spectrum and coupling spectrum that all include the outer scale. Our oceanic spectrum agrees better with the experimental data than others do from low wave-number regions to high wave-number regions. Based on our proposed oceanic spectrum, we derive the analytical expression of the scintillation index of Gaussian-beam wave and investigate the influence of the light source and the channel parameters on the scintillation index of Gaussian-beam wave. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007656DOI Listing

Deriving inherent optical properties from classical water color measurements: Forel-Ule index and Secchi disk depth.

Opt Express 2019 Mar;27(5):7642-7655

Secchi disk depth (ZSD) and Forel-Ule index (FUI) are the two oldest and easiest measurements of water optical properties based on visual determination. With an overarching objective to obtain water inherent optical properties (IOPs) using these historical measurements, this study presents a model for associating remote-sensing reflectance (Rrs) with FUI and ZSD. Based upon this, a scheme (FZ2ab) for converting FUI and ZSD to absorption (a) and backscattering coefficients (bb) is developed and evaluated. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007642DOI Listing

Synthesis of modified carbon dots with performance of ultraviolet absorption used in sunscreen.

Opt Express 2019 Mar;27(5):7629-7641

The research and development of non-toxic, broad-spectrum and environmentally friendly ultraviolet absorbers remains no significant progress in recent years. We found that the ultraviolet absorption spectra can be regulated through modification of functional groups on carbon dots surface, and the modified carbon dots exhibiting good stability and functions of sunscreen (Sun protection actor reaches to 22) and anti-aging properties were experimentally demonstrated. Moreover, we figured out the ultraviolet absorption mechanism of carbon dots for the first time and confirmed the existence of non-fluorescent radiation energy traps. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007629DOI Listing

Photonic technologies for autonomous cars: feature introduction.

Opt Express 2019 Mar;27(5):7627-7628

Photonic technologies that support the low cost manufacturing needed for automotive sensors have experienced explosive developments in recent years. To date most commercially available lidar system have been direct detection time-of-flight (ToF) sensors operating at 905 nm using mechanical mirrors for beam steering. However, these sensors suffer from important drawbacks. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=oe-27-5-7627
Publisher Site
http://dx.doi.org/10.1364/OE.27.007627DOI Listing
March 2019
5 Reads

Nonsequential double ionization by co-rotating two-color circularly polarized laser fields.

Opt Express 2019 Mar;27(5):7616-7626

Nonsequential double ionization (NSDI) of Ar in co-rotating two-color circularly polarized (TCCP) laser fields is investigated with a three-dimensional classical ensemble model. Our numerical results indicate that co-rotating TCCP fields can induce NSDI by recollision process, while the yield is an order of magnitude lower than counter-rotating case. NSDI yield in co-rotating TCCP fields strongly depends on field ratio of the two colors and achieves its maximum at a ratio of 2. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007616DOI Listing
March 2019
2 Reads

Infinite deflectometry enabling 2π-steradian measurement range.

Opt Express 2019 Mar;27(5):7602-7615

We present a novel deflectometry implementation termed Infinite Deflectometry. The technique provides a full aperture surface reconstruction sag map of freeform surfaces, including previously challenging to measure optics such as highly convex surfaces. The method relies on the creation of a virtual source enclosure around the tested optic, which creates a virtual 2π-steradian measurement range. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007602DOI Listing

Periodic revival of frustrated two-photon creation via interference.

Opt Express 2019 Mar;27(5):7593-7601

It has been known that suitably placed external mirrors can enhance and suppress emission of entangled photon pairs in spontaneous parametric down-conversion (SPDC), known as frustrated two-photon creation via interference. In this work, we report periodic revival of frustrated two-photon creation via interference with SPDC pumped by a continuous-wave (cw) multi-mode laser. As the mirrors are translated relative to the position of the SPDC source, the effect of frustrated two-photon creation via interference gradually dies off. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007593DOI Listing

High power monolithic tapered ytterbium-doped fiber laser oscillator.

Opt Express 2019 Mar;27(5):7585-7592

In the power scaling of monolithic fiber lasers, the fiber nonlinear effects and transverse mode instability are main limitations. The tapered gain fiber has a longitudinally varying mode area, which has the advantage of mitigating fiber nonlinear effects. However, the transverse mode instability (TMI) was seldom reported in the tapered fiber lasers at high average power levels. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007585DOI Listing
March 2019
1 Read

High-accuracy VLC-based indoor positioning system using multi-level modulation.

Opt Express 2019 Mar;27(5):7568-7584

In this study, a novel high-precision positioning algorithm was proposed by using Visible Light Communication (VLC) with only a simple and single receiver. The received voltage-level difference with multi-level modulation was adopted as the input variable, in order to minimize the negative consequences of noise. Then, the relationship between the received voltage-level difference, noise, and position was developed based on the optical propagation model. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007568DOI Listing

Polyethersulfone optical fibers with thermally induced microbubbles for custom side-scattering profiles.

Opt Express 2019 Mar;27(5):7560-7567

Polyethersulfone (PES) optical fibers are drawn and thermally processed in order to generate variable side-illumination profiles. The thermal treatment allows microbubbles to be formed in an outer layer of the PES fiber, providing light scattering with controllable amplitudes (0.25-2. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007560DOI Listing

Full-field ultrafast oscilloscope based on temporal imaging.

Opt Express 2019 Mar;27(5):7545-7559

As the ultrafast laser has been developed, the measurement of ultra-speed transient and dynamic processes has gained much attention. An ultrafast oscilloscope based on the optical stretch method is promising to address this problem, but the measurement is restricted to the temporal profile. This means that the temporal phase is lost. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007545DOI Listing

Suppression of reflected side lobes in narrow-band X-ray multilayer coatings.

Opt Express 2019 Mar;27(5):7537-7544

We present an analytical method for the design of narrow-band X-ray multilayer coatings having greatly reduced reflected side-lobe intensity, for the realization of X-ray mirrors that have improved spectral purity. The method uses a specific variation of the individual layer thicknesses as a function of depth in the multilayer stack, derived from Laplace transform analysis of the multilayer's reflectance profile. The design process and mathematical foundations are outlined. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007537DOI Listing

Self-calibration of in situ monoscopic deflectometric measurement in precision optical manufacturing.

Opt Express 2019 Mar;27(5):7523-7536

Accurate in situ measurement of complex optical surfaces is desired for precision manufacturing, and deflectometry is a promising measuring method. However, deflectometry's measurement accuracy depends heavily on the geometric calibration's reliability. Existing calibration methods suffer from the limitations of low efficiency, complicated operations, and expensive equipment. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007523DOI Listing

Compact compound-eye imaging module based on the phase diffractive microlens array for biometric fingerprint capturing.

Opt Express 2019 Mar;27(5):7513-7522

A compound-eye imaging system based on the phase diffractive microlens array as a compact observation module is proposed. As compared with the refractive microlens in common compound-eye imaging systems, the diffractive microlens is a flat imaging optics featuring high relative aperture, thin component thickness and compatibility with lithography techniques. As an application, a compact fingerprint imaging module was demonstrated using this compound-eye imaging system. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=oe-27-5-7513
Publisher Site
http://dx.doi.org/10.1364/OE.27.007513DOI Listing
March 2019
2 Reads

Near-field Fourier ptychography: super-resolution phase retrieval via speckle illumination.

Opt Express 2019 Mar;27(5):7498-7512

High spatial resolution is the goal of many imaging systems. While designing a high-resolution lens with diffraction-limited performance over a large field of view remains a difficult task, creating a complex speckle pattern with wavelength-limited spatial features is easily accomplished with a simple random diffuser. With this observation and the concept of near-field ptychography, we report a new imaging modality, termed near-field Fourier ptychography, to address high-resolution imaging challenges in both microscopic and macroscopic imaging settings. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007498DOI Listing
March 2019
3.488 Impact Factor

Hyperbolic sine-correlated beams.

Authors:
Zhangrong Mei

Opt Express 2019 Mar;27(5):7491-7497

An explicit expression is given for the cross-spectral density that characterizes a new family of partially coherence sources with hyperbolic sine correlated function. Beam conditions for such sources are established. The propagation properties of such partially coherent beams are studied by numerical simulations. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007491DOI Listing

Magneto-optic pyrochlore ceramics of TbHfO for Faraday rotator.

Opt Express 2019 Mar;27(5):7485-7490

In the first demonstration of the Faraday effect in an optical-grade TbHfO (THO) ceramic, its optical properties and the Verdet constant's wavelength dependence were evaluated at room temperature. The transmittance loss of this material was equally low as for the terbium gallium garnet, a well-known magneto-optic material. The Verdet constant at 1064 nm was 50. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007485DOI Listing
March 2019
1 Read

Versatile total angular momentum generation using cascaded J-plates.

Opt Express 2019 Mar;27(5):7469-7484

Optical elements coupling the spin and orbital angular momentum (SAM/OAM) of light have found a range of applications in classical and quantum optics. The J-plate, with J referring to the photon's total angular momentum (TAM), is a metasurface device that imparts two arbitrary OAM states on an arbitrary orthogonal basis of spin states. We demonstrate that when these J-plates are cascaded in series, they can generate several single quantum number beams and versatile superpositions thereof. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007469DOI Listing

Spontaneous parametric down-conversion of photons at 660 nm to the terahertz and sub-terahertz frequency range.

Opt Express 2019 Mar;27(5):7458-7468

We report on spontaneous parametric down-conversion (SPDC) in periodically poled lithium niobate (PPLN) using 660 nm pump wavelength and the type 0 phase-matching condition to the terahertz and even sub-terahertz frequency range. Detection of the frequency-shifted signal photons is achieved by using highly efficient and narrowband volume Bragg gratings and an uncooled sCMOS camera. The acquired frequency-angular spectrum shows backward and forward generation of terahertz and sub-terahertz photons by SPDC, as well as up-conversion and higher order quasi phase-matching (QPM). Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007458DOI Listing

395 nm GaN-based near-ultraviolet light-emitting diodes on Si substrates with a high wall-plug efficiency of 52.0%@350 mA.

Opt Express 2019 Mar;27(5):7447-7457

The high-performance 395 nm GaN-based near-ultraviolet (UV) light emitting diodes (LEDs) on Si substrates have been obtained by designing an AlN buffer layer to decrease the dislocations density of the GaN layer. By adopting a multi-layer structure with a high- and low-V/III ratio alternation, a high-quality AlN buffer layer has been obtained with a small full-width at half-maximum (FWHM) for AlN(0002) X-ray rocking curve (XRC) of 648 arcsec and a small root-mean-square roughness of 0.11 nm. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007447DOI Listing
March 2019
1 Read
3.488 Impact Factor

Off-beam QEPAS sensor using an 11-μm DFB-QCL with an optimized acoustic resonator.

Opt Express 2019 Mar;27(5):7435-7446

An off-beam quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor was designed for ethylene detection using a distributed-feedback quantum cascade laser (QCL) operating in the mid-infrared around 11 μm. The acoustic microresonator configuration was experimentally optimized using an original open-cell photoacoustic setup with a MEMS microphone. Correction factors based on theoretical acoustic models were introduced in order to accurately describe the response of millimeter-sized acoustic resonators. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=oe-27-5-7435
Publisher Site
http://dx.doi.org/10.1364/OE.27.007435DOI Listing
March 2019
9 Reads

Accumulation and directionality of large spontaneous emission enabled by epsilon-near-zero film.

Opt Express 2019 Mar;27(5):7426-7434

We demonstrate the spectral accumulation of large spontaneous emission (SE) for nanocavities with different sizes in the coupled Ag nanorod and epsilon-near-zero (ENZ) film system. This effect originates from the slowing down of the spectral shift of resonant nanocavities at the wavelength where the permittivity of the substrate vanishes, i.e. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=oe-27-5-7426
Publisher Site
http://dx.doi.org/10.1364/OE.27.007426DOI Listing
March 2019
3 Reads

Real-time dynamic strain sensing in optical fibers using artificial neural networks.

Opt Express 2019 Mar;27(5):7405-7425

We propose to use artificial neural networks (ANNs) for raw measurement data interpolation and signal shift computation and to demonstrate advantages for wavelength-scanning coherent optical time domain reflectometry (WS-COTDR) and dynamic strain distribution measurement along optical fibers. The ANNs are trained with synthetic data to predict signal shifts from wavelength scans. Domain adaptation to measurement data is achieved, and standard correlation algorithms are outperformed. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007405DOI Listing

Independently tunable multi-band and ultra-wide-band absorbers based on multilayer metal-graphene metamaterials.

Opt Express 2019 Mar;27(5):7393-7404

Dynamically and independently tunable absorbers based on multilayer metal-graphene metamaterials are proposed to achieve multi-band and ultra-wide-band absorbing properties at mid-infrared frequencies. Dual-band, triple-band and even more bands absorption can be arbitrarily customized by etching the appropriate number of tandem gold strips in each meta-molecule, as well as stacking multiple metal-graphene layers. Through tuning the Fermi energy level of the graphene in each metal-graphene layer separately, the multiple absorption resonances can be dynamically and independently adjusted. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007393DOI Listing

Fast and robust quantum control for multimode interactions using shortcuts to adiabaticity.

Opt Express 2019 Mar;27(5):7384-7392

Adiabatic quantum control is a very important approach for quantum physics and quantum information processing (QIP). It holds the advantage with robustness to experimental imperfections but accumulates more decoherence due to the long evolution time. Here, we propose a universal protocol for fast and robust quantum control in multimode interactions of a quantum system by using shortcuts to adiabaticity. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007384DOI Listing

On-chip plasmon-induced transparency in THz metamaterial on a LiNbO subwavelength planar waveguide.

Opt Express 2019 Mar;27(5):7373-7383

We experimentally demonstrate on-chip plasmon-induced transparency at THz frequencies using a meta-structure deposited on a 50 μm-thick dielectric subwavelength waveguide. The obvious plasmon-induced transparency results from strong coupling between the respective modes of a cut wire and a double-gap split ring resonator. The simulation and experimental results are consistent. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=oe-27-5-7373
Publisher Site
http://dx.doi.org/10.1364/OE.27.007373DOI Listing
March 2019
9 Reads
3.488 Impact Factor

Ultra-sharp asymmetric Fano-like resonance spectrum on Si photonic platform.

Opt Express 2019 Mar;27(5):7365-7372

In this paper, we report the generation of an ultra-sharp asymmetric resonance spectrum through Fano-like interference. This generation is accomplished by weakly coupling a high-quality factor (Q factor) Fabry-Pérot (FP) cavity and a low-Q factor FP cavity through evanescent waves. The high-Q FP cavity is formed by Sagnac loop mirrors, whilst the low-Q one is built by partially transmitting Sagnac loop reflectors. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007365DOI Listing
March 2019
4 Reads

Nonlinear FM-AM conversion due to stimulated Brillouin scattering.

Opt Express 2019 Mar;27(5):7354-7364

We report an effect potentially harmful occurring in regenerative amplifiers due to stimulated Brillouin scattering (SBS). Most high energy laser facilities use phase-modulated pulses to prevent the transverse SBS effect in large optical components and to smooth the focal spot on target. However, this kind of pulse format may undergo a detrimental effect known as frequency modulation to amplitude modulation (FM-AM) conversion in the presence of spectral distortions. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007354DOI Listing

Multiple EIT and EIA in optical microresonators.

Opt Express 2019 Mar;27(5):7344-7353

Multiple-path interference plays a fundamental role in classical and quantum physics. In this work, we propose two general schemes to realize multiple electromagnetically induced transparency (EIT) and electromagnetically induced absorption (EIA) in coupled microresonators and optomechanical systems. We give explicit physical descriptions and find out that these two schemes are essentially equivalent to each other. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007344DOI Listing
March 2019
1 Read

Laser-induced electrical signal filtering by multilayer reduced graphene oxide decorated with Au nanoparticles.

Opt Express 2019 Mar;27(5):7330-7343

Nanoscale plasmonic particles represent a crucial transformation on optical and electronic properties exhibited by advanced materials. Herein are reported remarkable interferometric optical effects with dependence on polarization for filtering or modulating electronic signals in multilayer nanostructures. Metallic nanoparticles were incorporated in randomly distributed networks of reduced graphene oxide by an in-situ vapor-phase deposition method. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007330DOI Listing

Quadrature phase-shifted optical demodulator for low-coherence fiber-optic Fabry-Perot interferometric sensors.

Opt Express 2019 Mar;27(5):7319-7329

We demonstrate a quadrature phase-shifted optical demodulation scheme for low-coherence fiber-optic Fabry-Perot interferometric sensors. The main part of the demodulator is a fiber-optic Mach-Zehnder interferometer (MZI) constructed with a 1 × 2 fiber coupler, a 3 × 3 fiber coupler, and fiber delay lines. This configuration allows us to generate quadrature phase-shifted interference signals simultaneously, thus eliminating the problem of ambiguous phase discrimination. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007319DOI Listing

Experimental electric field visualisation of multi-mode dynamics in a short cavity swept laser designed for OCT applications.

Opt Express 2019 Mar;27(5):7307-7318

An experimental study into the modal dynamics of a short cavity, fast frequency-swept laser is presented. This commercially available external cavity swept source is designed for use in optical coherence tomography (OCT) applications and displays a number of dynamic lasing regimes during the course of the wavelength sweep. Interferometric full electric field reconstruction is employed, allowing for measurement of the laser operation in a time-resolved, single-shot manner. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007307DOI Listing

Depth-graded Mo/Si multilayer coatings for hard x-rays.

Opt Express 2019 Mar;27(5):7291-7306

This manuscript presents the first systematic study of non-periodic, broadband Mo/Si multilayer coatings with and without B C interface barrier layers for hard x-ray applications with large field of view. The photon energy of operation in this work is 17.4 keV, the Mo Kα emission line. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007291DOI Listing
March 2019
3.488 Impact Factor

Negative axicon tip-based fiber optic interferometer cavity sensor for volatile gas sensing.

Opt Express 2019 Mar;27(5):7277-7290

In this research work we demonstrated negative axicon optical fiber tip filled with Polydimethylsiloxane (PDMS) as a sensor platform for volatile organic gases detection at room temperature. The response of the sensor was measured with various Volatile Organic Compounds (VOCs) such as Chloroform, Hexane, Isopropanol, Acetone, Toluene and Methanol in the concentration ranging from 5 to 200 ppm. The corresponding sensitivity and limit of detection (LOD) of the developed sensor for the measured VOCs were observed between the order of around 23. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007277DOI Listing
March 2019
1 Read
3.488 Impact Factor

Efficient optical trapping with cylindrical vector beams.

Opt Express 2019 Mar;27(5):7266-7276

Radially and azimuthally polarized beams can create needle-like electric and magnetic fields under tight focusing conditions, respectively, and thus have been highly recommended for optical manipulation. There have been reports on the superiority of these beams over the conventional Gaussian beam for providing a larger optical force in single beam optical trap. However, serious discrepancies in their experimental results prevent one from concluding this superiority. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007266DOI Listing

In situ 3D reconfigurable ultrasonically sculpted optical beam paths.

Opt Express 2019 Mar;27(5):7249-7265

We demonstrate that optical beams can be spatially and temporally shaped in situ by forming 3D reconfigurable interference patterns of ultrasound waves in the medium. In this technique, ultrasonic pressure waves induce a modulated refractive index pattern that shapes the optical beam as it propagates through the medium. Using custom-designed cylindrical ultrasonic arrays, we demonstrate that complex patterns of light can be sculpted in the medium, including dipole and quadrupole shapes. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007249DOI Listing

Three-dimensional super-resolution imaging of live whole cells using galvanometer-based structured illumination microscopy.

Opt Express 2019 Mar;27(5):7237-7248

Imaging and tracking three-dimensional (3D) nanoscale organizations and functions of live cells is essential for biological research but it remains challenging. Among different 3D super-resolution techniques, 3D structured illumination microscopy (SIM) has the intrinsic advantages for live-cell studies; it is based on wide-field imaging and does not require high light intensities or special fluorescent dyes to double 3D resolution. However, the 3D SIM system has developed relatively slowly, especially in live imaging. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.27.007237DOI Listing
March 2019
2 Reads