Photonic Bandgap Fibers | previous | next | feedback |
Definition: a special type of photonic crystal fibers, relying on photonic bandgaps
Photonic bandgap fibers constitute a special type of photonic crystal fibers. In contrast to the situation in an ordinary optical fiber, the guiding mechanism in a photonic bandgap fiber is not based on an increased refractive index of the fiber core, but on a photonic bandgap. Essentially, the guidance is provided by a kind of two-dimensional Bragg mirror structure around the core, which does not allow light to escape in the radial direction – at least in one or a few a limited wavelength ranges.
The refractive index of the core itself can be lower than that of the cladding structure; it can even be hollow, so that its refractive index is that of air (close to 1). As most of the light is then propagating in air rather than in glass (air-guiding fibers), such kinds of hollow-core photonic bandgap fibers have a very weak nonlinearity, which makes them promising e.g. for the dispersive compression of ultrashort pulses with high peak power, or for the delivery of high-power laser beams. However, photonic bandgap fibers are generally more difficult to produce due to their tight fabrication tolerances, have a limited bandwidth for low-loss transmission, and often exhibit relatively high propagation losses.
Bibliography
| [1] | R. F. Cregan et al., “Single-mode photonic band gap guidance of light in air”, Science 285, 1537 (1999) (first hollow-core PCF) |
| [2] | K. Saitoh and M. Koshiba, “Photonic bandgap fibers with high birefringence”, IEEE Photon. Technol. Lett. 14, 1291-1293 (2002) |
| [3] | P. J. Roberts et al., “Ultimate low loss of hollow-core photonic crystal fibres”, Opt. Express 13 (1), 236 (2005) |
| [4] | G. Ren et al., “Low-loss all-solid photonic bandgap fiber”, Opt. Lett. 32 (9), 1023 (2007) |
| [5] | S. Février et al., “High-power photonic-bandgap fiber laser”, Opt. Lett. 33 (9), 989 (2008) |
See also: photonic crystal fibers, fibers
Category: fibers and other waveguides
