We present theoretical and experimental results of a polarization splitter device that consists photonic crystal (PhC) slab, which exhibits large reflection coefficient for TE high transmission TM polarization. The slab is embedded in PhC tile operating the self-collimation mode. Embedding polarization-discriminating with identical lattice symmetry suppresses in-plane diffraction losses at PhC-non-PhC interface. optimization interface thereby decoupled from polarizing function. Transmissions...

Photonic crystals (PhCs) act on light in two different ways: confinement and modification of propagation. Both phenomena rely the complex interplay between multiply scattered waves that can form what is known as a Bloch mode. Here, we present technique allows direct imaging modes, both real space k-space. The gives access to location field maxima inside PhC, dispersion relation, equifrequency surfaces, well reflection transmission coefficients. Our key advance retrieve desired information...

Abstract We explore the use of micro-transfer printing (µTP) technology to integrate thin lithium niobate (LN) films onto silicon nitride (SiN) waveguides, facilitating development compact electro-optical modulators. Three modulator architectures are investigated: Mach-Zehnder interferometer (MZI), Fabry-Perot (FP) resonator, and side-coupled FP resonators. By acting as a photonic molecule, proposed coupled resonators enable improved spectral engineering with new functionalities while...

Abstract Laser-based mid-infrared (mid-IR) photothermal spectroscopy (PTS) represents a selective, fast, and sensitive analytical technique. Recent developments in laser design permits the coverage of wider spectral regions combination with higher power, enabling for qualitative reconstruction broadband absorption features, typical liquid or solid samples. In this work, we use an external cavity quantum cascade (EC-QCL) that emits pulsed mode region between 5.7 6.4 µm (1770–1560 cm −1 ), to...

Using near-field scanning microscopy, we demonstrate that a 15-µm zone plate fabricated in 70-nm chromium film sputtered on glass substrate and having focal length outermost zone's width equal to the incident wavelength λ = 532 nm, focuses circularly polarized Gaussian beam into circular subwavelength spot whose diameter at fullwidth of half-maximum intensity is FWHM=0.47λ.This value near-accurate agreement with FDTD-aided numerical estimate FWHM=0.46λ.When focusing linearly along y-axis, an...

We present a polarization converter using one-dimensional grating principles. The device is based on slanted slots etched deeply into an InP/InGaAsP heterostructure. Almost complete conversion, with 14 dB extinction ratio, observed for less than 2 microm long.

We have fabricated high-quality planar photonic crystal defect waveguides in InP/InGaAsP material. Using Fourier analysis of the Fabry-Pérot fringes obtained transmission, we derive propagation losses. Values as small 1.8 dB/mm for consisting three rows missing holes (W3) were measured. believe that reduction losses is due to high quality etching carried out using a beam voltage–current ratio regime chemically assisted ion-beam etching.

We examine the surface recombination rate in quantum-dot semiconductor lasers and determine diffusion length (1.0 μm) and, for first time, provide a value velocity (5×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> cm/s) material. As result of strong carrier confinement dots, these values are much lower than comparable quantum-well xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> cm/s 5 μm, respectively) allowing creation narrow...

We designed, fabricated, and characterized a thin metalens in an amorphous silicon film of diameter 30 µm, focal length equal to the incident wavelength 633 nm. The lens is capable simultaneously manipulating state polarization phase light. converts linearly polarized beam into radially light, producing subwavelength focus. When illuminated with Gaussian beam, produces spot whose size at full-width half-maximum intensity 0.49λ 0.55λ (λ wavelength). experimental results are good agreement...

We report the design, fabrication, and characterization of a new nanophotonic device comprising two-dimensional photonic crystal (PhC) lens size 3x4 microm fabricated in silicon-on-insulator. The PhC is put at output planar waveguide width 4.5 to couple light into 1 microm, with two waveguides being length 5 mm. A off-axis displacement smaller leads an 8-fold reduction intensity, which means that focal spot silicon less than microm. simulation has shown maximal transmittance 1.55 coupling...

We have investigated a four-sector transmission polarization converter (4-SPC) for wavelength of 633 nm, that enables the conversion linearly polarized incident beam into mixture and azimuthally beams. It was numerically shown by placing Fresnel zone plate focal length 532 nm immediately after 4-SPC, light can be focused an oblong subwavelength spot whose size is smaller than diffraction limit (with width breadth, respectively, measuring FWHM = 0.28λ 0.45λ, where λ stands full-width at half...

We investigate etching conditions for photonic crystals (PhCs) in InGaAsP/InP and AlGaAs/GaAs using a new regime of CAIBE operation. show that the beam voltage-current ratio is critical obtaining high material/mask selectivity. For one-dimensional PhCs, i.e., air slots, selectivities 22:1 50:1 were achieved InP GaAs, respectively, very voltage (about 1500 V) low current 10 mA). Etched features observed to be smooth, edge roughness was low. Two-dimensional PhCs etched under similar achieving...

We retrieve the dispersion properties of photonic crystal waveguides near band edge with high experimental accuracy. The diagram waveguide modes in complex-valued plane is directly measured far field by using a Fourier space imaging technique. show that investigation $k$ provides clear signature transition between propagating, evanescent, and localized modes. It allows us to determine impact structural disorder dissipation on group velocity propagating wave slow light regime.

We present theoretical and experimental results for compact slanted gratings vertical coupling between single-mode fiber InP-InGaAsP waveguides. The maximum calculated efficiency is 59%. have measured a of 16% 10-mum-long grating

We have designed and fabricated a 100 μm×100 μm four-sector binary subwavelength reflecting polarization microconverter in gold film. Using finite-difference time-domain-aided numerical simulations experiments, the micropolarizer was shown to convert an incident linearly polarized Gaussian beam of wavelength 532 nm into azimuthally beam. Conditions for generating on-axis regions nonzero intensity when using propagating optical vortices with different initial were deduced. By putting spiral...

A binary subwavelength four-zone transmission element with metasurface for simultaneously controlling the polarization and phase of laser light was synthesized characterized. The manufactured in a silicon film spattered on glass substrate. It performs near-field conversion linearly polarized incident beam into near azimuthally shift π at diametrically opposite points beam. In far field, converted produces an intensity maximum center, as opposed to minimum from

We present a method for creating hard mask the dry etching of microphotonic structures and devices. demonstrate that spin-on glass [hydrogen silsesquioxane (HSQ)] has sufficient etch resistance to allow creation high-quality, deeply etched photonic crystals. Furthermore, HSQ is more favorable active devices than plasma-enhanced chemical-vapor deposition (PECVD) silica, as less damage incurred. It also an economic convenient replacement PEVCD in crystal fabrication. examine this show it can...

In this paper, we have designed and fabricated a four-zone binary subwavelength reflective micropolarizer. The 100×100-µm micropolarizer grating was synthesized by electron-beam lithography. FDTD-based numerical simulation experimental characterization shown the to be capable of transforming linearly polarized incident Gaussian beam wavelength 532 nm into an azimuthally beam.

This paper presents the experimental results for compact (20- and 40-/spl mu/m-long) electrooptically tuned deeply etched Fabry-Perot (F-P) filters in InP-based material. Both quantum-confined Stark effect (QCSE) carrier-injection (C-I) effects were implemented to achieve tunability of these microcavity filters. Red blue shifts transmission peaks order 1 2 nm observed both effects, limitations on C-I due thermal are clearly demonstrated discussed. The advantages disadvantages tuning...

In this work, we combine Lithium Niobate on insulator with a silicon nitride layer to form strip-loaded waveguides that can take advantage of the strong nonlinear optical coefficients lithium niobate and high refractive contrast ease processing nitride. We describe design fabrication Fabry-Perot cavity formed by Distributed Bragg Reflectors. discuss trade-offs implicit in realisation such microcavities nature demonstrate an experimental quality factor 2300, which is our knowledge, highest...

Using electronic beam lithography and reactive ion etching, a metalens is manufactured in thin layer of amorphous silicon 130-nm depth, 30-µm diameter, 633-nm focal length (equal to the illumination wavelength). The composed 16 sectored subwavelength binary gratings with 220-nm period. uniqueness this that when illuminated by left-handed circularly polarized light, it capable generating vortex topological charge 2, second-order cylindrical vector linearly light. Both for linear circular...