We propose methods to perform intensity interferometry of photons having two different wavelengths. Distinguishable particles typically cannot interfere with each other, but we overcome that obstacle by processing the via entanglement and projection so they lead same final state at detection apparatus. Specifically, discuss how quasi-phase-matched nonlinear crystals can be used convert a quantu...

Abstract The optical elements comprised of sub-diffractive light scatterers, or metasurfaces, hold a promise to reduce the footprint and unfold new functionalities devices. A particular interest is focused on metasurfaces for manipulation phase amplitude beams. Characterisation can be performed using interferometry, which, however, may cumbersome, specifically in infrared (IR) range. Here, we r...

In optics, the superposition of two or more light beams at any point over space can produce the apparition of interference fringes. When these fringes are applied to resolve a problem in industry or they are related with some property of an investigation matter of interest in some area of physics, chemistry, biology, etc., the evaluation of them is a very necessary task. One of the most used me...

An interference fringe modulation skewing effect in white-light vertical scanning interferometry that can produce a batwings artifact in a step height measurement is described. The skewing occurs at a position on or close to the edge of a step in the sample under measurement when the step height is less than the coherence length of the light source used. A diffraction model is used to explain t...

The usual technique for measuring vibration within the cochlear partition is heterodyne interferometry. Recently, spectral domain phase microscopy (SDPM) was introduced and offers improvements over standard heterodyne interferometry. In particular, it has a penetration depth of several mm due to working in the infrared range, has narrow and steep optical sectioning due to using a wideband light...

Infrared vibrational scattering scanning near-field optical microscopy (s-SNOM) has emerged as a new frontier in imaging science due to its potential to provide nanoscale spatially resolved chemical spectroscopy for the investigation of molecular, soft-matter, and biological materials. As a phase-sensitive technique able to yield the full complex dielectric function of materials, different inte...

Recent progress has been made in the development of low cost, portable, meter-class light bucket telescopes, as well as low cost, lightweight foam glass and spin-cast epoxy mirrors. One of many astronomical applications of light bucket telescopes is stellar intensity interferometry, pioneered by Hanbury Brown in the 1960s. Major advances in detectors, electronics, and computers now allow much f...

In the area of Fluids Mechanics, detailed analysis and characterization of complex, unsteady flows require non-invasive optical methods to measure smaller and smaller quantities over space or time, or even both at once. Therefore, many researchers have spent considerable time over the last fifty years to develop metrology tools adapted to quantitative flow visualization. Some of these methods s...

The propagation of light in nonperiodic quasicrystals is studied by ultrashort pulse interferometry. Samples consist of multilayer dielectric structures of the Fibonacci type and are realized from porous silicon. We observe mode beating and strong pulse stretching in the light transport through these systems, and a strongly suppressed group velocity for frequencies close to a Fibonacci band gap...

The spatial distribution of surface plasmon scattering from a single nanoparticle changes dramatically near a metal surface as a result of interference from the direct scattered light and indirect scattered light from the mirror reflection. The unique interference patterns have been reproduced by simulations based on Huygens-Fresnel wave propagation theory. The large spectral width of the surfa...