[INVITED] Optical microfibre devices

Abstract

In the last decade optical fibre tapers with micrometer diameter (often called microfibers) have been investigated for numerous applications ranging from sensing to wavelength convertors, telecom and optical manipulation. This paper reviews the various applications of microfibres. 1. Optical microfibres Although microfibers with diameters comparable to the wavelength have been manufactured for nearly half of a century [1], their application in devices has been limited because of the perceived difficulty to achieve low-loss propagation [2]. Microfibres have been manufactured from a variety of different materials including silica [3-8], silicon [9,10], phosphate [11], tellurite [11], lead-silicate [12], bismuthate [12] and chalcogenide glasses [13] and a variety of polymers [14-19]. Most of the microfibers exhibited an irregular profile along their length which resulted in high propagation losses in devices. In the last decade the use of the flame-brushing technique [3-8] allowed to manufacture microfibers with losses smaller than 0.01dB/mm, sufficiently low for the manufacture of devices for sensing, comms, wavelength conversion and optical manipulation. Optical microfibers (OMs) are optical fibre tapers with diameters comparable to the wavelength of light propagating in them. They generally fabricated by tapering optical fibres and therefore result connected to conventional optical fibres by transition regions (Fig. 1). If the transition region has a suitably small angle, a single mode launched in the optical fibre pigtail core is adiabatically transferred in a single mode guided by the cladding/external medium interface and no power occurs into other modes.

Label-Free Biological and Chemical Sensing Using Whispering Gallery Mode Optical Resonators: Past, Present, and Future

“…A partial list includes microrings [40,41], disks [12], knots/coils [42], bottles [43], droplets [44], goblets [45], rolled-up microcavities [46], bubbles [47], polystyrene microspheres [48,49], asymmetric cavities [50], cylinders [51], vertically coupled race track resonators [52], nearly spherical diamond resonators [53], crystalline CaF 2 cavities [54], and liquid-core optical ring resonators (LCORR) [55]. White-light WGM resonators have also been developed [56].…”

Effect of agarose concentration on coated micro‐bottle resonators for humidity detection

“…4,5 Fiber optics sensing media show promise as potential solution to these limitation due to fiber optics immunity to electromagnetic interference, and affordability. [6][7][8] Optical micro resonators (OMR) are a promising choice of fiber optics sensor. OMR have varied applications in plasmonic devices, lasers and sensors by creating continuous internal reflections.…”

Optical Wave Guiding and Spectral Properties of Micro/Nanofibers Used for Quantum Sensing and Quantum Light Generation

“…The strong radial confinement much longer than the Rayleigh range of a focused Gaussian beam has made it possible to efficiently couple atoms to the fiber mode via the evanescent field [9][10][11][12][13]. With these waveguiding properties, MNFs, so far, have been used for broad application in optical sensing [14][15][16][17][18][19][20][21][22][23], optical trapping [24,25], evanescent field coupling [26], and quantum optics [27,28]. Also, the flexibility and mechanical strength of MNFs have been able to offer great advantage to demonstrate various microstructures as sensing head, such as loop, coil, and optical coupler [29][30][31].…”