Dr. Kanishka Tankala Profile

Dr. Kanishka Tankala

Vice President Specialty Fiber Products at Coherent

SPIE Involvement:

Author | Editor

Publications (32)

Proceedings Article | 9 March 2023 Presentation

High concentration large-mode-area Tm-doped double-clad fiber for high efficiency operation

Stefan Gausmann, Benoit Faugas, Joshua Bradford, Mark Goldsmith, Adrian Carter, Kanishka Tankala, Clemence Jollivet

Proceedings Volume 12400, 124000L (2023) https://doi.org/10.1117/12.2650126

KEYWORDS: Thulium, Single mode fibers, Manufacturing, Fiber lasers

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Proceedings Article | 4 March 2022 Presentation

Novel extra-large mode area Yb-doped fibers for high energy and high average power industrial laser systems

Joshua Bradford, Mike Conroy, Mark Goldsmith, Adrian Carter, Kanishka Tankala, Clémence Jollivet

Proceedings Volume PC11981, PC1198105 (2022) https://doi.org/10.1117/12.2609159

KEYWORDS: Optical fibers, Laser systems engineering, Fiber lasers, Thermal efficiency, Particles, Optical amplifiers, Materials processing, Manufacturing, Fiber amplifiers, Energy efficiency

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Proceedings Article | 21 April 2017 Presentation

Dispersion tailored non-PM and PM fibers for 2 microns ultrafast fiber lasers (Conference Presentation)

Clémence Jollivet, Daniel Jeannotte, Peyman Ahmadi, Adrian Carter, Kanishka Tankala

Proceedings Volume 10083, 100830E (2017) https://doi.org/10.1117/12.2250543

KEYWORDS: Optics manufacturing, Waveguides, Optical fibers, Dispersion, Ultrafast phenomena, Fiber lasers, Picosecond phenomena, Phase modulation, Pulsed laser operation, Laser systems engineering

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Proceedings Article | 7 March 2017 Presentation + Paper

Design optimization of Tm-doped large-mode area fibers for power scaling of 2 µm lasers and amplifiers

C. Jollivet, K. Farley, M. Conroy, H. Dabhi, J. Edgecumbe, A. Carter, K. Tankala

Proceedings Volume 10083, 100830I (2017) https://doi.org/10.1117/12.2250549

KEYWORDS: Fiber amplifiers, Amplifiers, Specialty optical fibers, Doping, Refractive index, Fusion splicing, Optical fibers, Optical amplifiers, Waveguides, Diffusion, Optical testing, Laser systems engineering, Thermal effects

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Proceedings Article | 22 April 2016 Paper

Specialty flat-top beam delivery fibers with controlled beam parameter product

C. Jollivet, K. Farley, M. Conroy, J. Abramczyk, S. Belke, F. Becker, K. Tankala

Proceedings Volume 9727, 97270T (2016) https://doi.org/10.1117/12.2209348

KEYWORDS: Optical fibers, Beam shaping, Beam controllers, Specialty optical fibers, Beam delivery, Beam homogenizers, High power fiber lasers, Diodes, Materials processing, Multimode fibers, Optical testing, Laser applications, Standards development, Semiconductor lasers

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Proceedings Article | 11 March 2016 Paper

Mechanical reliability of double clad fibers in typical fiber laser deployment conditions

Michael Walorny, Jaroslaw Abramczyk, Nick Jacobson, Kanishka Tankala

Proceedings Volume 9728, 97283A (2016) https://doi.org/10.1117/12.2212992

KEYWORDS: Optical fibers, Reliability, Fiber lasers, High power lasers, Factor analysis, Manufacturing, Fiber amplifiers, Laser development, Corrosion, Laser manufacturing, Failure analysis, Chemical oxygen iodine lasers, Absorption

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Proceedings Article | 11 March 2016 Paper

Novel beam delivery fibers for delivering flat-top beams with controlled BPP for high power CW and pulsed laser applications

C. Jollivet, K. Farley, M. Conroy, J. Abramczyk, S. Belke, F. Becker, K. Tankala

Proceedings Volume 9728, 97283D (2016) https://doi.org/10.1117/12.2212705

KEYWORDS: Beam delivery, Specialty optical fibers, Fiber lasers, Laser applications, Materials processing, Continuous wave operation, Beam controllers, High power fiber lasers, Laser systems engineering, Optical fibers, Signal attenuation, Laser cutting, Beam shaping

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Proceedings Article | 15 April 2015 Paper

Long-term optical reliability and lifetime predictability of double clad fibers

Jaroslaw Abramczyk, Harish Govindarajan, Wells Cunningham, Douglas Guertin, Kanishka Tankala

Proceedings Volume 9344, 934415 (2015) https://doi.org/10.1117/12.2080855

KEYWORDS: Signal attenuation, Humidity, Optical fibers, Reliability, Polymers, Fiber lasers, Lithium, Glasses, Data modeling, Optical coatings

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Proceedings Article | 12 March 2014 Paper

Optical fiber designs for beam shaping

Kevin Farley, Michael Conroy, Chih-Hao Wang, Jaroslaw Abramczyk, Stuart Campbell, George Oulundsen, Kanishka Tankala

Proceedings Volume 8961, 89612U (2014) https://doi.org/10.1117/12.2041992

KEYWORDS: Beam delivery, Beam shaping, Fiber lasers, Optical fibers, Near field, Gaussian beams, Laser systems engineering, Optical design, Laser applications, Refractive index

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Proceedings Article | 7 March 2014 Paper

Performance of kW class fiber amplifiers spanning a broad range of wavelengths: 1028~1100nm

Ye Huang, John Edgecumbe, Jianwu Ding, Roger Holten, Peyman Ahmadi, Chih-Hao Wang, Cyril Guintrand, Kevin Farley, Scott Christensen, Kanishka Tankala

Proceedings Volume 8961, 89612K (2014) https://doi.org/10.1117/12.2042002

KEYWORDS: Amplifiers, Fiber amplifiers, Absorption, Polarization, Fiber lasers, Phase modulation, Single mode fibers, High power fiber amplifiers, Continuous wave operation, Optical amplifiers

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SPIE Journal Paper | 1 November 2011

Reliability of low-index polymer coated double-clad fibers used in fiber lasers and amplifiers

Kanishka Tankala, Douglas Guertin, Jaroslaw Abramczyk, Nils Jacobson

OE, Vol. 50, Issue 11, 111607, (November 2011) https://doi.org/10.1117/12.10.1117/1.3615653

KEYWORDS: Optical fibers, Polymers, Reliability, Optical coatings, Signal attenuation, Humidity, Polymer optical fibers, Fiber lasers, Cladding, Fiber amplifiers

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Proceedings Article | 11 February 2011 Paper

A monolithic thulium doped single mode fiber laser with 1.5ns pulsewidth and 8kW peak power

Jianwu Ding, Bryce Sampson, Adrian Carter, Chiachi Wang, Kanishka Tankala

Proceedings Volume 7914, 79140X (2011) https://doi.org/10.1117/12.876867

KEYWORDS: Fiber lasers, Pulsed laser operation, Thulium, Absorption, Semiconductor lasers, Signal generators, Laser applications, Single mode fibers, Cladding, Ions

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Proceedings Article | 11 February 2011 Paper

Reliability and photodarkening in 790nm-pumped 2μm fiber lasers

A. Carter, B. Samson, J. Ding, G. Frith, K. Tankala

Proceedings Volume 7914, 79140J (2011) https://doi.org/10.1117/12.879060

KEYWORDS: Fiber lasers, Reliability, Continuous wave operation, Thulium, Laser systems engineering, Pulsed laser operation, LASIK, Laser applications, Laser resonators, Fiber Bragg gratings

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Proceedings Article | 4 May 2010 Paper

kW level narrow linewidth Yb fiber amplifiers for beam combining

Victor Khitrov, Kevin Farley, Ryan Leveille, Joshua Galipeau, Imtiaz Majid, Scott Christensen, Bryce Samson, Kanishka Tankala

Proceedings Volume 7686, 76860A (2010) https://doi.org/10.1117/12.862648

KEYWORDS: Fiber amplifiers, Optical amplifiers, Amplifiers, Fiber lasers, Ytterbium, Laser damage threshold, Absorption, Diodes, Optical properties, Laser development

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Proceedings Article | 17 February 2010 Paper

Mitigation of photodegradation in 790nm-pumped Tm-doped fibers

G. Frith, A. Carter, B. Samson, J. Faroni, K. Farley, K. Tankala, G. Town

Proceedings Volume 7580, 75800A (2010) https://doi.org/10.1117/12.846230

KEYWORDS: Thulium, Fiber lasers, Absorption, Upconversion, Ions, Silica, Optical fibers, Energy transfer, Chromium, Reliability

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Proceedings Article | 12 May 2009 Paper

400W monolithic high efficiency 2 µm MOPA

S. Christensen, T. Ehrenreich, V. Khitrov, K. Tankala, A. Carter, B. Samson

Proceedings Volume 7325, 73250C (2009) https://doi.org/10.1117/12.819311

KEYWORDS: Amplifiers, Diodes, Signal attenuation, Fiber amplifiers, Phase modulation, Free space, Oscillators, Semiconductor lasers, Standards development

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Proceedings Article | 2 October 2008 Paper

Latest developments in 790nm-pumped Tm-doped fibre laser systems for DIRCM applications

G. Frith, T. McComb, B. Samson, W. Torruellas, A. Carter, J. Farroni, K. Farley, K. Tankala

Proceedings Volume 7115, 711507 (2008) https://doi.org/10.1117/12.800415

KEYWORDS: Optical amplifiers, Fiber lasers, Fiber amplifiers, Laser systems engineering, Absorption, Amplifiers, Directed infrared countermeasures, Laser applications, Cladding, Pulsed laser operation

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Proceedings Article | 22 February 2008 Paper

50W single-mode linearly polarized high peak power pulsed fiber laser with tunable ns-μs pulse durations and kHz-MHz repetition rates

V. Khitrov, B. Samson, D. Machewirth, K. Tankala

Proceedings Volume 6873, 68730C (2008) https://doi.org/10.1117/12.763198

KEYWORDS: Pulsed laser operation, Amplifiers, Laser applications, Pulsed fiber lasers, Phase modulation, Fiber lasers, Diodes, Molybdenum, Distortion, Tunable lasers

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Proceedings Article | 10 May 2007 Paper

High peak power eye-safe coherent EYDFA laser source

Y. Chen, B. Matheson, W. Torruellas, J. Faroni, N. Jacobson, K. Tankala

Proceedings Volume 6552, 65520T (2007) https://doi.org/10.1117/12.721458

KEYWORDS: Fiber lasers, Laser systems engineering, Optical amplifiers, Fiber amplifiers, Laser sources, Diffraction, Semiconductor lasers, Refractive index, LIDAR, Erbium

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Proceedings Article | 22 February 2007 Paper

Current developments in high-power, monolithic, polarization maintaining fiber amplifiers for coherent beam combining applications

D. Machewirth, Q. Wang, B. Samson, K. Tankala, M. O'Connor, M. Alam

Proceedings Volume 6453, 64531F (2007) https://doi.org/10.1117/12.712691

KEYWORDS: Optical amplifiers, Fiber amplifiers, Phase modulation, High power fiber amplifiers, Diodes, Optical isolators, Amplifiers, Polarization maintaining fibers, Geometrical optics, Active optics

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Proceedings Article | 20 February 2007 Paper

High-peak power-pulsed single-mode linearly-polarized LMA fiber amplifier and Q-switch laser

V. Khitrov, B. Samson, D. Machewirth, D. Yan, K. Tankala, A. Held

Proceedings Volume 6453, 645305 (2007) https://doi.org/10.1117/12.712341

KEYWORDS: Fiber amplifiers, Fiber lasers, Q switching, Q switched fiber lasers, Oscillators, Phase modulation, Amplifiers, Pulsed laser operation, Optical amplifiers, Laser applications

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Proceedings Article | 23 February 2006 Paper

1 kW, 15μJ linearly polarized fiber laser operating at 977 nm

V. Khitrov, D. Machewirth, B. Samson, K. Tankala

Proceedings Volume 6102, 610222 (2006) https://doi.org/10.1117/12.646715

KEYWORDS: Fiber lasers, Ytterbium, Phase modulation, Semiconductor lasers, Pulsed laser operation, Pulsed fiber lasers, Diodes, Wavelength division multiplexing, Laser applications, Polarization

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Proceedings Article | 23 February 2006 Paper

High peak power ytterbium doped fiber amplifiers

W. Torruellas, Y. Chen, B. McIntosh, J. Farroni, K. Tankala, S. Webster, D. Hagan, M. Soileau, M. Messerly, J. Dawson

Proceedings Volume 6102, 61020N (2006) https://doi.org/10.1117/12.646571

KEYWORDS: Ytterbium, Silica, Fiber amplifiers, Cladding, Optical damage, Refractive index, Optical amplifiers, Optical fibers, Semiconductor lasers, Fiber lasers

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Proceedings Article | 23 February 2006 Paper

New developments in high power eye-safe LMA fibers

K. Tankala, B. Samson, A. Carter, J. Farroni, D. Machewirth, N. Jacobson, U. Manyam, A. Sanchez, M-Y. Chen, A. Galvanauskas, W. Torruellas, Y. Chen

Proceedings Volume 6102, 610206 (2006) https://doi.org/10.1117/12.646663

KEYWORDS: Thulium, Optical fibers, Absorption, Ytterbium, Erbium, Cladding, Ions, Silica, Quantum efficiency, Glasses

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Proceedings Article | 7 February 2006 Paper

Optical damage measurements for high peak power ytterbium doped fiber amplifiers

S. Webster, F.C. McDonald, A. Villanger, M.J. Soileau, E.W. Van Stryland, D.J. Hagan, B. McIntosh, W. Torruellas, J. Farroni, K. Tankala

Proceedings Volume 5991, 599115 (2006) https://doi.org/10.1117/12.639287

KEYWORDS: Ytterbium, Silica, Transmittance, Cladding, Germanium, Fiber amplifiers, Sensors, Microscopes, Laser induced damage, Optical testing

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Proceedings Article | 22 April 2005 Paper

Linearly polarized high-power fiber lasers with monolithic PM-LMA-fiber and LMA-grating based cavities and their use for nonlinear wavelength conversion

V. Khitrov, B. Samson, U. Manyam, K. Tankala, D. Machewirth, S. Heinemann, C. Liu, A. Galvanauskas

Proceedings Volume 5709, (2005) https://doi.org/10.1117/12.590825

KEYWORDS: Fiber lasers, Polarization, Fiber Bragg gratings, High power fiber lasers, Continuous wave operation, Diffraction, Laser resonators, Chemical oxygen iodine lasers, Diodes, Laser applications

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Proceedings Article | 21 February 2005 Paper

Damage mechanisms in components for fiber lasers and amplifiers

Adrian Carter, Bryce Samson, Kanishka Tankala, David Machewirth, Victor Khitrov, Upendra Manyam, Francois Gonthier, Francois Seguin

Proceedings Volume 5647, (2005) https://doi.org/10.1117/12.592015

KEYWORDS: Fiber lasers, Cladding, Coating, Glasses, Reliability, Polymers, Fiber Bragg gratings, Interfaces, Continuous wave operation, Fiber coupled lasers

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Proceedings Article | 8 October 2004 Paper

Continued advancements in the design of double clad fibers for use in high output fiber lasers and amplifiers

Adrian Carter, Kanishka Tankala, Bryce Samson, David Machewirth, Victor Khitrov, Upendra Manyam

Proceedings Volume 5662, (2004) https://doi.org/10.1117/12.596360

KEYWORDS: Optical fibers, Fiber lasers, Birefringence, Fiber amplifiers, Polarization, Cladding, Phase modulation, Ytterbium, Single mode fibers, Nonlinear dynamics

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Fiber lasers have a number of distinct advantages over their more conventional solid state laser alternatives. These advantages include size, reliability, wavelength selectivity, heat dissipation, wall plug efficiency and operational cost. Furthermore they can be operated without the need for active cooling or optical alignment. Consequently the market for these more traditional laser sources are beginning to be eroded by the emergence of fiber lasers. In 1999 high power fiber lasers became a reality, with the world's first single-mode fiber laser exhibiting in excess of 100W cw output. However it was soon recognized that conventional small core, high NA fiber designs were not appropriate to applications requiring further scaling of the output power. More specifically it was found that the maximum achievable output power in such fibers were restricted by a fundamental susceptibility to optical nonlinearities, including stimulated Raman scattering (SRS), stimulated Brillouin scattering (SBS) and self-phase modulation. In order to overcome the limitations imposed by these parasitic nonlinear processes, it has been necessary to develop fibers with high rare-earth dopant concentrations in relatively large core, low numerical aperture fibers. These so-called large mode area (LMA) fibers are directly responsible for the recent explosion in demonstrated diffraction-limited beam quality output powers, now approaching the kW-level from a single fiber. To further scale the output power it is necessary to combine the output of several fiber lasers. Indeed, for a number of industrial and military applications it is desirable to scale the total output power to between several and hundreds of kW's. It is therefore advantageous to be able to coherently combine the beams from multiple fibers and this it turns makes it desirable for the fiber to also be polarization maintaining. This provides yet another layer of complexity to the fiber design but such fibers are now a commercial reality. In this paper we review the recent and ongoing advantages in fiber design that is facilitating the development and production of lasers and amplifiers with ever increasing output powers.

Proceedings Article | 14 June 2004 Paper

The road to kilowatt fiber lasers

Adrian Carter, Bryce Samson, Kanishka Tankala, David Machewirth, Upendra Manyam, Jaroslaw Abramczyk, Julia Farroni, Douglas Guertin, Nils Jacobson

Proceedings Volume 5350, (2004) https://doi.org/10.1117/12.533134

KEYWORDS: Fiber lasers, Birefringence, Cladding, Phase modulation, Glasses, Manufacturing, Diodes, Ytterbium, Fiber coupled lasers, Roads

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Proceedings Article | 7 June 2004 Paper

Large-mode-area double-clad fibers for pulsed and CW lasers and amplifiers

David Machewirth, Victor Khitrov, Upendra Manyam, Kanishka Tankala, Adrian Carter, Jaroslaw Abramczyk, Julia Farroni, Douglas Guertin, Nils Jacobson

Proceedings Volume 5335, (2004) https://doi.org/10.1117/12.528056

KEYWORDS: Optical fibers, Ytterbium, Cladding, Phase modulation, Amplifiers, Absorption, Fiber lasers, Reliability, Optical testing, Chemical oxygen iodine lasers

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Proceedings Article | 8 March 2004 Paper

Small form-factor PANDA-type HiBi fiber for sensing applications

Mansoor Alam, Douglas Guertin, Julia Farroni, Jaroslaw Abramczyk, Nick Jacobson, Kanishka Tankala

Proceedings Volume 5272, (2004) https://doi.org/10.1117/12.514751

KEYWORDS: Birefringence, Fiber optics sensors, Interferometry, Fiber optic gyroscopes, Polarization maintaining fibers, Tolerancing, Polarization, Sensors, Geometrical optics, Temperature metrology

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Proceedings Article | 3 July 2003 Paper

PM double-clad fibers for high-power lasers and amplifiers

Kanishka Tankala, Adrian Carter, David Machewirth, Julia Farroni, Jaroslaw Abramczyk, Upendra Manyam

Proceedings Volume 4974, (2003) https://doi.org/10.1117/12.501679

KEYWORDS: Optical fibers, Birefringence, Phase modulation, Amplifiers, High power lasers, Cladding, Polarization, Luminescence, Ytterbium, Fiber lasers

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