Related papers: Micro-lensed single-mode optical fiber with high n…
We describe a micro-fabrication method to create concave features with ultra-low surface roughness in silica, either on the end facets of optical fibers or on flat substrates. The machining uses a single focused CO2 laser pulse. Parameters…
This paper presents a theoretical design of chalcogenide glass based tapered microstructured optical fiber (MOF) to generate high power parabolic pulses (PPs) at the mid-IR wavelength (~ 2 {\mu}m). We optimize fiber cross-section by the…
Future quantum technology relies crucially on building quantum networks with high fidelity. To achieve this challenging goal, it is of utmost importance to connect single quantum systems in a way such that their emitted single-photons…
Efficient power coupling between on-chip guided and free-space optical modes requires precision spatial mode matching with apodized grating couplers. Yet, grating apodizations are often limited by the minimum feature size of the fabrication…
Tapered optical fibers (TOFs) with sub-wavelength-diameter waists, known as optical nanofibers, are powerful tools for interfacing quantum emitters and nanophotonics. These applications demand stable polarization of the fiber-guided light…
Modern extreme adaptive optics (AO) systems achieving diffraction-limited performance open up new possibilities for instrumentation. Especially important for the fields of spectroscopy and interferometry is that it enables the prospect to…
We propose and demonstrate two methods for modal decomposition in multi-mode fibres. Linearly polarized modes propagating in a slightly multi-mode fibre are easily retrieved from intensity measurements at the fibre output surface. The first…
Laser science has tackled physical limitations to achieve higher power, faster and smaller light sources. The quest for ultra-compact laser that can directly generate coherent optical fields at the nano-scale, far beyond the diffraction…
Optical fiber is a well-established efficient way to guide and manipulate light and allowing high bandwidth optical transmission for long distance communication with low attenuation. Although a dielectric optical waveguide is efficient for…
This paper presents the work achieved for the manufacturing and characterization of first single-mode waveguides to be used as modal filters for nulling interferometry in the mid-infrared range [4-20 um]. As very high dynamic range is…
Optical nanofibers (ONF) of subwavelength dimensions confine light in modes with a strong evanescent field that can trap, probe, and manipulate nearby quantum systems. To measure the evanescent field and propagating modes, and to optimize…
We demonstrate a conceptually new mechanism for sub-wavelength focusing at optical frequencies based upon the use of nano-hole quasi-periodic arrays in metal screens. Using coherent illumination at 660 nm and scanning near-field optical…
A conceptual design work and a basic experimental study of a new beam profile monitor have been performed. The monitor will be used to measure emittance of an electron beam in the ATF damping ring at KEK, in which the transverse beam size…
We report on microlasers based on high-quality micropillars with lasing on whispering-gallery modes. Usage of low-absorbing Al$\scriptsize 0.2$Ga$\scriptsize 0.8$As\Al$\scriptsize 0.9$Ga$\scriptsize 0.1$As distributed Bragg reflectors as…
The optical transmission and reflection in between two metalized optical fiber tips is studied in the optical near-field and far-field domains. Besides aluminum-coated tips for near-field scanning optical microscopy (NSOM), specifically…
A metasurface lens (meta-lens) bends light using nanostructures on a flat surface. Macroscopic meta-lenses (mm- to cm-scale diameter) have been quite difficult to simulate and optimize, due to the large area, the lack of periodicity, and…
Thanks to the compact design and multi-functional light-manipulation capabilities, reconfigurable metalenses, which consist of arrays of sub-wavelength meta-atoms, offer unique opportunities for advanced optical systems, from microscopy to…
We experimentally demonstrate that side-coupling of coplanar bent optical fibers can induce a high Q-factor whispering gallery mode (WGM) optical microresonator. To explain the effect, we consider WGMs with wavelengths close to the cutoff…
A nanoparticle detection scheme with single particle resolution is presented. The sensor contains only a taper fiber thus offering the advantages of compactness and installation flexibility. Sensing method is based on monitoring the…
We demonstrate fiber Fabry-Perot (FFP) cavities with concave mirrors that can be operated at cavity lengths as large as 1.5mm without significant deterioration of the finesse. This is achieved by using a laser dot machining technique to…