# Fileset

[lp10fuse+sem4.pdf](https://mdr.nims.go.jp/filesets/2092f740-6ab6-47e9-a735-0f91b6e2272e/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

Untitled19th Laser Physics Workshop (LPHYS’10) 9.3.3 (1)'&$%Light & Voids of Fiber Fuse:precise comparison ofin situ image & fused fibersShin-ichi TODOROKI NIMS JapanLaser~1m/s 7W����Video 1Slide 1'&$%Introduction Fiber fuse papersSlide 219th Laser Physics Workshop (LPHYS’10) 9.3.3 (2)'&$%Introduction Related historySlide 3'&$%Introduction Fiber fuse researchTheoretical ExperimentalMacroscopicMicroscopic• Practical research• Termination• Simulation• Dissipative soliton• Capillary instability • In situ observationShuto (’03),Yakovlenko,AkhmedievKashyap (’87), Hand,Dianov, ...,Abedin, ...Atkins (’03),YakovlenkoTodoroki (’04),BufetovSlide 419th Laser Physics Workshop (LPHYS’10) 9.3.3 (3)'&$%OVERVIEWLight & Voids of Fiber FuseReviewWhat is known about its macroscopic behavior?ModelWhat did I found 5 years ago?EvidenceWhat is newly found with a new video camera?Slide 5'&$%ReviewWhat is known about its macroscopic behavior?PropagationIgnitionTerminationSlide 619th Laser Physics Workshop (LPHYS’10) 9.3.3 (4)'&$%Propagation Dissipative soliton~WLaser lightOptical fiber Hollow damageSlide 7'&$%Propagation Solitons: Classical vs. DissipativeEnergy / MassTransportationTemperatureReaction zoneINOUTSlide 819th Laser Physics Workshop (LPHYS’10) 9.3.3 (5)'&$%Propagation Black body radiation200 400 600 800Wavelength (nm)Plasma radiation (a.u.)38W9W3W10500K7900K4700KEx: 1.08 µmDianov (’06)Silica glass fiberFiber laserSpectrometerSlide 9'&$%Propagation Fusing speed vs. Pump powerSlide 1019th Laser Physics Workshop (LPHYS’10) 9.3.3 (6)'&$%Propagation Simulation• Shuto (’03)• Yakovlenko (’04)• Akhmediev (’08)Dissipative soliton TemperatureReaction zoneINOUTTt = χαI︸︷︷︸+ D∂2T∂x2− k(T − T0)︸ ︷︷ ︸Light-induced heat Diffusion + RelaxationSlide 11'&$%ReviewWhat is known about its macroscopic behavior?PropagationIt runs like a grass fire, balancing btw input & output.IgnitionTerminationSlide 1219th Laser Physics Workshop (LPHYS’10) 9.3.3 (7)'&$%Ignition~WHeat~1m/sSlide 13'&$%Ignition Demo videoGlass ferrule Co oxide powder1.48 µm9W����Video 2Slide 1419th Laser Physics Workshop (LPHYS’10) 9.3.3 (8)'&$%Ignition Heat induced absorptionSiO2∆−→ SiO + 12O2 (Shuto ’03)Slide 15'&$%Ignition Supporting evidenceSilica glass fibers:• O2 in the voids⇐= Raman microscopy (Kashyap ’88)SiO2∆−→ SiO + 12O2• Densification⇐= Refractive index ր (Dianov ’92)∆nmax ∼ 0.012Slide 1619th Laser Physics Workshop (LPHYS’10) 9.3.3 (9)'&$%ReviewIt runs like a grass fire, balancing btw input &output.PropagationIt runs like a grass fire, balancing btw input & output.IgnitionHeat generates SiO that triggers a positive feedback.TerminationSlide 17'&$%Termination How can we do?LightSourceTemperatureReaction zoneINOUTSlide 1819th Laser Physics Workshop (LPHYS’10) 9.3.3 (10)'&$%Termination Demo videoLaser1.48µmHeat & Light ����Video 3Slide 19'&$%Termination Enhance the outputat special devices,• Mode field expansionHand (’89)⇒Yanagi (’03)• Pressure leakage(?)in a Hole-Assisted FiberTakenaga (’08)Dianov(’04)Slide 2019th Laser Physics Workshop (LPHYS’10) 9.3.3 (11)'&$%Termination Reduce the inputafter detecting the ignition byLightSourceSlide 21'&$%Termination Reduce the inputafter detecting the ignition by• Reflection from voids, fc = ν/p• Doppler shift, fD = 2nν/λLightsourcePDSpectrumanalyzer1%0-50-1001.00.50Frequency (MHz)�Intensity (dBm) ƒcƒD5 msAbedin (’09)Slide 2219th Laser Physics Workshop (LPHYS’10) 9.3.3 (12)'&$%ReviewWhat is known about its macroscopic behavior?PropagationIt runs like a grass fire, balancing btw input & output.IgnitionHeat generates SiO that triggers a positive feedback.TerminationDevices are designed to break input-output balance.Slide 23'&$%OVERVIEWLight & Voids of Fiber FuseReviewDissipative soliton: useful to recognize its behaviorModelWhat did I found 5 years ago?EvidenceWhat is newly found with a new video camera?Slide 2419th Laser Physics Workshop (LPHYS’10) 9.3.3 (13)'&$%ModelWhat did I found 5 years ago?PatternHow the void train changes its shape with input power?OriginWhat is revealed with an ultra-high speed camera?ArchaeologyWhat has been concluded from damage patterns?Slide 25'&$%Pattern Laser power dependence9 W SMF-28, 1.48 µm7 W: ↔ 20 µm5 W3.5 W2 W1.5 W1.3 W1.2 WSlide 2619th Laser Physics Workshop (LPHYS’10) 9.3.3 (14)'&$%Pattern Front part of the void train9 W SMF-28 1.48 µm7 W: ↔ 20 µm5 W3.5 W2 W1.5 W1.3 W1.2 WSlide 27'&$%Pattern Capillary instability• Rayleigh instabilityAtkins(’03)• Charge repulsion induced on plasma-melt interfaceYakovlenko(’04)Slide 2819th Laser Physics Workshop (LPHYS’10) 9.3.3 (15)'&$%ModelWhat did I found 5 years ago?PatternBullet train appears when the input is more than 2W.OriginWhat is revealed with an ultra-high speed camera?ArchaeologyWhat has been concluded from damage patterns?Slide 29'&$%Origin Ultra-high speed videography20041024-step4µs / frame1µs-exposure    w/ ND filters128x16Photron• Wavelength: 380–790nm����Video 4Slide 3019th Laser Physics Workshop (LPHYS’10) 9.3.3 (16)'&$%Origin Periodicity appears with a tail1.48µm5W3.5W2W1.5WSlide 31'&$%Origin Difficult to detect light modulationsdue to poor resolutionSlide 3219th Laser Physics Workshop (LPHYS’10) 9.3.3 (17)'&$%ModelWhat did I found 5 years ago?PatternBullet train appears when the input is more than 2W.OriginTailed plasma leaves periodic bullet-shaped voids.ArchaeologyWhat has been concluded from damage patterns?Slide 33'&$%Archaeology Moves with constant velocityduring one void generation (20 µs)1.48µm 7WSlide 3419th Laser Physics Workshop (LPHYS’10) 9.3.3 (18)'&$%Archaeology Sorting by time reveals the action1.48µm 7W����Video 5(1)(2)(3)Distance from the top (4)(5)(6)(a)(b)(c)Temperature ViscositySlide 35'&$%ModelWhat did I found 5 years ago?PatternBullet train appears when the input is more than 2W.OriginTailed plasma leaves periodic bullet-shaped voids.ArchaeologyExtended tail is casted off to form one of the bullets.Slide 3619th Laser Physics Workshop (LPHYS’10) 9.3.3 (19)'&$%OVERVIEWLight & Voids of Fiber FuseReviewDissipative soliton: useful to recognize its behaviorModelTailed plasma must be the source of bullet-like voids.EvidenceWhat is newly found with a new video camera?Slide 37'&$%EvidenceWhat is newly found with a new video camera?High-resolutionWhat is the new findings about the modulated light?ExaminationWhat’s the relation btw the modulation & the bullets?ReliabilityHow reliable the animation of void formation is?Slide 3819th Laser Physics Workshop (LPHYS’10) 9.3.3 (20)'&$%High-resolution Improved performance2004 20091024-step 4096-step1.4µs Photron����Video 6Slide 39'&$%High-resolution Scattering from the voidsSMF-28e 1.48µm 9WSlide 4019th Laser Physics Workshop (LPHYS’10) 9.3.3 (21)'&$%High-resolution Quenching behaviorsSMF-28e 1.48µm 9WSlide 41'&$%EvidenceWhat is newly found with a new video camera?High-resolutionModulated light goes out at between the voids.ExaminationWhat’s the relation btw the modulation & the bullets?ReliabilityHow reliable the animation of void formation is?Slide 4219th Laser Physics Workshop (LPHYS’10) 9.3.3 (22)'&$%Examination Reversed bullet appearsnear a HI 1060 / SMF-28e splicing point,1.07µm 9WMFD(µm) 6.2 → 9.2 (1.31µm)����Video 7Slide 43'&$%Examination Different quenching behaviorsSlide 4419th Laser Physics Workshop (LPHYS’10) 9.3.3 (23)'&$%EvidenceWhat is newly found with a new video camera?High-resolutionModulated light goes out at between the voids.ExaminationShifting direction agrees with the bullet direction.ReliabilityHow reliable the animation of void formation is?Slide 45'&$%Reliability Quenched voids vs. in-situ image1.48µm 9W����Video 8Slide 4619th Laser Physics Workshop (LPHYS’10) 9.3.3 (24)'&$%EvidenceWhat is newly found with a new video camera?High-resolutionModulated light goes out at between the voids.ExaminationShifting direction agrees with the bullet direction.ReliabilityMelt bridge motion is not found in in situ image.Slide 47'&$%SUMMARYLight & Voids of Fiber FuseReviewDissipative soliton: useful to recognize its behaviorModelTailed plasma must be the source of bullet-like voids.EvidenceBullet-like shape is formed after plasma extinction.Slide 4819th Laser Physics Workshop (LPHYS’10) 9.3.3 (25)'&$%Acknowledgments• Photron Co. Ltd.• Dr. Evgueni M. Dianov• the late Dr. Sergei I. YakovlenkoSlide 49