Potentialities of glass air-clad micro- and nanofibers for nonlinear optics

Optical microfiber passive components

“…Microfibers are also ideal for exciting the surface second harmonic owing to their high surface field amplitude. Indeed, the second harmonic was observed in references due to the close proximity between certain third‐ and second‐harmonic phase‐match diameters – for example, in the HE 12 (3ω) and HE 21 (2ω) modes phase match at and 524 nm, respectively, thus allowing the second harmonic to be detected albeit at an order of magnitude smaller.…”

“…(a) Three experimental output pulses from a loop resonator at different detunings and (b) the corresponding resonator transmission spectrum, with the wavelengths used in (a). Source: . (c) Simulated hysteresis characteristics of a lossy three‐turn MCR at three wavelengths from small detuning (dashed line) to large detuning (dotted line) from resonance.…”

Optical microfibers and nanofibers

“…Owing to the miniaturized mode area [11,18] and engineerable dispersion [11,16,211], MNFs exhibit enhanced nonlinear effects such as supercontinuum generation [9,15,17,112,113,118,119,182], third-harmonic generation [183][184][185][186][187][188], bistability [46,160], two-photon absorption [189,190] with relatively low optical power. To obtain higher optical nonlinearity, many other materials with high nonlinearities (e.g., leadsilicate, bismuth-silicate, As 2 Se 3 chalcogenide) have been drawn into MNFs for various purposes [82,191].…”

Nonlinear microfiber loop resonators for resonantly enhanced third harmonic generation

“…Indeed, third harmonic generation (THG) in OMs has been investigated [2][3][4][5][6][7] wherein the intermodal phase matching is satisfied at certain OM diameters when the effective indices n eff of the fundamental pump and higher order harmonic mode are roughly equal. In this work, we utilize such OMs to form loop resonators [8] in which the recirculation of the pump light near resonance enhances the third harmonic conversion and reduces the required pump power; a mechanism recently used in microtoroids [9] and ring resonators [10].…”

“…In this work, we utilize such OMs to form loop resonators [8] in which the recirculation of the pump light near resonance enhances the third harmonic conversion and reduces the required pump power; a mechanism recently used in microtoroids [9] and ring resonators [10]. The presence of THG in loop resonators has previously only been noted as a side effect during pulse shaping experiments [6]. Here, we model the nonlinear characteristics and experimentally demonstrate the resonant THG enhancement for silica loop resonators pumped at 1550 nm.…”