# Fileset

[lphys10.pdf](https://mdr.nims.go.jp/filesets/737373df-a578-4678-bd57-5eaf35b01775/download)

## Creator

[TODOROKI, Shin-ichi](https://orcid.org/0000-0003-3986-1900)

## Rights

[In Copyright](http://rightsstatements.org/vocab/InC/1.0/)

## Other metadata

[Light and voids of fiber fuse: precise comparison of in situ image and fused fibers](https://mdr.nims.go.jp/datasets/ed562308-01c3-4b99-ab37-dcc6f5d58f5c)

## Fulltext

Light and voids of fiber fuse: precise comparison of in situ image and fused fibersFiber LasersLight and voids of fiber fuse:precise comparison of in situ image and fused fibersShin-ichi TodorokiNational Institute for Materials Science,Namiki 1-1, Tsukuba, Ibaraki 305-0044, JapanFax: +81 29 854 9060 E-mail: TODOROKI.Shin-ichi©a nims.go.jpThe damped oscillation of a fiber fuse light emission does not overlap the scattering pattern ofthe following periodic voids. This may be because the melted glass surrounding the quenchedplasma shifts to form bullet-like voids.In the two decades that have passed since the dis-Figure 1: Intensity profiles of in situ image of fiberfuse propagating through a single-mode optical fiberpumped by 9 W 1480 nm light (upper) and generatedvoids (lower). The vertical line interval is 22 µm.covery of the fiber fuse phenomenon [1, 2], significantprogress in laser technology has made it a real threatto optical communication systems. Since 2004, I havebeen investigating the nature of fiber fuse propagationthrough ultra-high speed videography [3, 4, 5]. This re-port discusses its modulated light emission in relation toits periodic void formation.A fiber fuse was initiated at the output end of acommercial single-mode optical fiber (SMF-28e) deliv-ering 9 W 1.48 nm light. Its propagation was observedthrough an ultra-high speed CCD camera (FASTCAMSA5, Photron Ltd., sensitivity range: 380–790 nm). Pic-tures with a resolution of 128×32 and a 4096-step gra-dation were taken every 1.43 µs with an exposure timeof 0.37 µs (see Fig. 1).The front two-thirds of the intensity profile (see ar-row a) remained constant during the propagation but theremainder was modulated periodically, i. e., a smallpeak appeared on the shoulder of the main peak andstayed in the same position until its extinction (see ar-row b). Although the interval of these small peaks wasthe same as that of the periodic voids (see the photo inFig. 1), the position of the emission decay did not coin-cide with the scattering points from the void train (see arrow c). Considering that the bullet-like shape of thevoids is formed by their asymmetric contraction caused by the pressure of the optical discharge [4], this shiftappears because the contraction occurs after the light extinction.[1] R. Kashyap and K. J. Blow, “Observation of catastrophic self-propelled self-focusing in optical fibres,” Electron.Lett., vol. 24, pp. 47–49, Jan. 1988.[2] D. P. Hand and P. St. J. Russell, “Solitary thermal shock waves and optical damage in optical fibers: the fiber fuse,”Opt. Lett., vol. 13, pp. 767–769, Sept. 1988.[3] S. Todoroki, “In-situ observation of fiber-fuse propagation,” Jpn. J. Appl. Phys., vol. 44, pp. 4022–4024, June2005.[4] S. Todoroki, “Origin of periodic void formation during fiber fuse,” Optics Express, vol. 13, pp. 6381–6389, Aug.2005.[5] http://www.youtube.com/Tokyo1406463http://dx.doi.org/10.1049/el:19880032http://dx.doi.org/10.1049/el:19880032http://dx.doi.org/10.1364/OL.13.000767http://dx.doi.org/10.1143/JJAP.44.4022http://dx.doi.org/10.1364/OPEX.13.006381http://www.youtube.com/Tokyo1406