A multicore optical fiber of an embodiment has a structure for simultaneously realizing low transmission loss, low fusion splicing loss, and low inter-core crosstalk. The multicore optical fiber includes a plurality of cores comprised of silica glass, a common cladding comprised of silica glass and surrounding the plurality of cores, and a resin coating surrounding the common cladding. The common cladding has a refractive index lower than a refractive index of the plurality of cores. Each of the plurality of cores contains chlorine at 10000 ppm or more in at least part thereof.

A low-crosstalk large-capacity few-mode optical fiber includes an optical fiber cladding. Few-mode units are arranged in the optical fiber cladding, each few-mode unit sequentially includes a few-mode fiber core, an inner cladding and a trench from inside to outside, and a high-refractive-index ring is arranged in the few-mode fiber core. The few-mode units include first few-mode subunits, second few-mode subunits and third few-mode subunits, where the first few-mode subunits, the second few-mode subunits and the third few-mode subunits are arranged at intervals. The first few-mode subunit includes a first few-mode fiber core, the second few-mode subunit includes a second few-mode fiber core, and the third few-mode subunit includes a third few-mode fiber core, the radii and refractive indexes of the first few-mode fiber cores, the second few-mode fiber cores and the third few-mode fiber cores being different, respectively.

A microstructured optical fiber for generating supercontinuum light. The optical fiber includes a core and a cladding region surrounding the core. The optical fiber includes a first fiber length section, a second fiber length section as well as an intermediate fiber length section between said first and second fiber length sections. The first fiber length section has a core with a first characteristic core diameter larger than about 7 μm. The second fiber length section has a core with a second characteristic core diameter, smaller than said first characteristic core diameter. The intermediate length section of the optical fiber includes a core which is tapered from said first characteristic core diameter to the second characteristic core diameter over a tapered length. Also, a supercontinuum light source including an optical fiber and a pump light source.

An all solid hybrid waveguiding structure provides large mode area, acceptable losses of the desired core mode and very high losses of the undesired next higher order mode in the core. Embodiments of the waveguide include a hybrid of low index barriers providing confinement by total internal reflection, and further include high index rings that support guided modes only at effective indices different from that of the desired core mode.

Certain exemplary embodiments can provide a system, machine, device, manufacture, circuit, and/or composition of matter, and/or a method for activities, that can comprise and/or relate to, a polarization-maintaining photonic crystal fiber comprising an elongated guiding core and/or an elongated photonic crystal cladding surrounding the core, the cladding defining a plurality of holes.

An optical waveguide is configured to guide an optical beam, and the optical waveguide includes a down-taper element configured to reduce a diameter of an incoming light beam having a random polarization; a dual-core directional coupler element configured to separate the incoming light beam into a horizontally-polarized beam and a vertically-polarized beam, each beam being confined in first and second cores, respectively; and a core fan-out element configured to increase a distance between the horizontally-polarized beam and the vertically-polarized beam upon exit from the core fan-out element. Each of the down-taper element, the dual-core directional coupler element, and the core fan-out element are 3-dimensional, 3D, printed using a single material.

A method of making a microstructured optical fiber including loading the core and cladding materials of the fiber with hydrogen and deuterium at a loading temperature; annealing the fiber at a selected temperature T.sub.anneal; pumping the fiber with radiation; and reducing the temperature of the fiber and storing the fiber at the reduced temperature before the step of pumping the fiber; and wherein the method allows the hydrogen and the deuterium to become bound to the core material and the cladding material.

The present disclosure provides a rollable optical fiber ribbon. The rollable optical fiber ribbon includes a plurality of optical fibers positioned along a longitudinal axis of the rollable optical fiber ribbon. In addition, the rollable optical fiber ribbon includes a matrix material covering the plurality of optical fibers. Each of the plurality of optical fibers is placed adjacent to other optical fiber of the plurality of optical fibers. Each of the plurality of optical fibers with a diameter of about 210±5 micron is spaced at a pitch in a range of about 250 microns to 255 microns. The rollable optical fiber ribbon is corrugated from a first side and a second side to enable rolling of the rollable optical fiber ribbon in circular fashion.

An optical fiber sensor includes an optical fiber. The optical fiber includes a cladding having a cladding refractive index, and a plurality of fiber cores embedded in the cladding and extending along a longitudinal axis of the optical fiber. The plurality of fiber cores include a first subset of at least one first fiber core and a second subset of at least one second fiber core. The at least one first fiber core has a first core refractive index different from the cladding refractive index and a first core radius in a direction transverse to the longitudinal axis. The at least one second fiber core has a second core refractive index different from the cladding refractive index and a second core radius transverse to the longitudinal axis. The second core refractive index and the second core radius differ from the first core refractive index and the first core radius such that a temperature sensitivity of the at least one second fiber core differs from the temperature sensitivity of the first fiber core.

The present application discloses a surface-enhanced Raman scattering (SERS)-active photonic crystal fiber (PCF) probe including a biopsy needle in the PCF probe for integrated sample collection and SERS sensing of one or more analytes comprised in the sample. The PCF comprises solid core and a cladding region surrounding the solid core, wherein the cladding region comprises air holes functionalised by metallic nanoparticles. The application also provides a method for detecting one or more analytes using the PCF probe as well as the use of the PCF probe for the detection of one or more analytes.