Browsing by Author "Ortaç, Bülend"
Now showing items 1-20 of 36
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130 nJ 77 fs dissipative soliton fiber laser
Baumgartl, M.; Ortaç, Bülend; Lecaplain, C.; Hideur, A.; Limpert J.; Tünnermann, A. (OSA, 2010)We report on ultrashort high-energy pulse generation from an all-normal-dispersion fiber oscillator. The watt-level laser directly emits chirped pulses with a duration of 1ps and 163nJ of pulse energy. These can be compressed ... -
915 nm pumped 1018 nm Yb-doped all-fiber high power fiber laser system
Midilli, Yakup; Efunbajo, O. Benjamin; Şimşek, Bartu; Ortaç, Bülend (Institute of Electrical and Electronics Engineers Inc., 2019)Fibers lasers have attracted great attention in the last decades and the power scaling has reached tens of kW levels. Especially with the tandem pump configuration, pumping the active medium with a pump laser light instead ... -
All-fiber all-normal-dispersion femtosecond laser with a nonlinear multimodal interference-based saturable absorber
Teğin, Uğur; Ortaç, Bülend (OSA - The Optical Society, 2018)In this Letter, we demonstrate, to the best of our knowledge, the first all-fiber all-normal-dispersion ytterbium-doped oscillator with a nonlinear multimodal interference-based saturable absorber capable of generating ... -
All-fiber all-normal-dispersion femtosecond laser with nonlinear multimodal interference-based saturable absorber
Teğin, Uğur; Ortaç, Bülend (Institute of Electrical and Electronics Engineers Inc., 2019)Chong et al. demonstrated a stable passively mode-locked all-normal-dispersion fiber laser and pulse generation is attributed to the strong spectral filtering of chirped pulses, dissipative soliton pulses [1]. In the ... -
An all-fiber ultra-low numerical aperture high power fiber MOPA system with an output power above 500 W
Midilli, Yakup; Ortaç, Bülend (Institute of Electrical and Electronics Engineers Inc., 2019)Optical fiber technology has been developed dramatically in the last two decades. Especially, the invention of the Large Mode Area (LMA) fibers has made a great impact, and consequently the power scale of the fiber lasers ... -
Cascaded Raman scattering based high power octave-spanning supercontinuum generation in graded-index multimode fibers
Teğin, Uğur; Ortaç, Bülend (Nature Publishing Group, 2018)A new method to generate multi-watt-level, octave-spanning, spectrally flat supercontinua stemmed from cascaded Raman scattering in graded-index multimode fibers is reported. Formation dynamics of supercontinua are ... -
CO2 polishing of femtosecond laser micromachined microfluidic channels
Serhatlıoğlu, Murat; Ortaç, Bülend; Elbuken, C.; Bıyıklı, Necmi; Solmaz, Mehmet E. (Optical Society of America, 2016)The CO2 polishing of femtosecond laser micromachined channels is studied. The surface quality before and after polishing is observed with naked eye and optical microscope. The method improves imaging of microspheres. -
A combinatorial buffered oxide etching method for high-power cladding light stripper
Yapar-Yıldırım, Elif; Karatutlu, Ali; Balk, Ekin Teslime; Midilli, Yakup; Ortaç, Bülend (Institute of Electrical and Electronics Engineers Inc., 2019)High-power fiber lasers have been applied in many areas due to their advantages such as high beam quality, compact structure, flexibility and high efficiency. However, the absorption of the pump light is limited and a ... -
Combined method for the fabrication of high-power cladding light stripper using a buffered oxide etchant
Yıldırım, Elif Yapar; Karatutlu, Ali; Balk, Ekin Teslime; Midilli, Yakup; Ortaç, Bülend (OSA - The Optical Society, 2019-08)Cladding light strippers (CLSs) are vital and one of the critical components for high-power fiber laser applications. In this study, we show the first studies of the formation mechanisms and optimum conditions of a CLS ... -
Cucurbit[7]uril-capped hybrid conjugated oligomer-gold nanoparticles for combined photodynamic-photothermal therapy and cellular imaging
Özkan, Melis; Tunç, İ.; Midilli, Y.; Ortaç, Bülend; Tuncel, Dönüş (ACS, 2020)Herein, hybrid nanoparticles composed of a redemitting conjugated oligomer (COL) and gold nanoparticles (Au-NPs) were prepared through a one-pot synthetic method in which the oligomer acts as a reducing agent as well as ... -
Demonstration of a novel cladding light stripper fabrication method based on poly (Chloro-P-Xylene) polymer material
Midilli, Yakup; Liman, Görkem; Demirel, Gökhan; Ortaç, Bülend (IEEE, 2021-09-30)Cladding light stripper (CLS) is a key component for high power fiber laser systems to remove the unwanted light sources out of the system effectively. If they cannot be removed out of the system, the quality of the laser ... -
Demonstration of an all-fiber ultra-low numerical aperture ytterbium-doped large mode area fiber in a master oscillator power amplifier configuration above 1 kW power level
Midilli, Yakup; Ortaç, Bülend (IEEE, 2020)We demonstrate an all-fiber ultra-low numerical aperture high power fiber laser system operating in the continuous-wave regime at a central wavelength of 1080 nm. A special Ytterbium-doped fiber preform has been designed ... -
Double ring firing single optical fiber deflector
Seymen, A. A.; Uzcengiz-Şimşek, Elif; Ӧzgür, E.; Ortaç, Bülend (Institute of Electrical and Electronics Engineers Inc., 2019)We report a novel fabrication method of double ring firing single optical fiber deflector. The fiber deflector is fabricated as a convergent cone having two different cone angles, by conventional mechanical polishing. The ... -
Enhanced light scattering with energy downshifting using 16 nm indium nitride nanoparticles for improved thin-film a-Si N-i-P solar cells
Chowdhury F.I.; İslam, K.; Alkış, Sabri; Ortaç, Bülend; Alevli, Mustafa; Dietz, N.; Okyay, Ali Kemal; Nayfeh, A. (Electrochemical Society Inc., 2015-05)In this work the effect of Indium nitride (InN) nanoparticles (NPs) on the performance of a-Si: H solar cells has been investigated. The average J<inf>sc</inf> of InN NPs coated cells was found 6.76 mA/cm2 which is 16.69% ... -
Femtosecond microjoule-Class ytterbium fiber lasers
Lecaplain, C.; Ortaç, Bülend; Machinet G.; Boullet J.; Baumgartl, M.; Schreiber, T.; Cormier, E.; Hideur, A. (Optical Society of America, 2011)We report the generation of 830 nJ energy from a mode-locked all-normal dispersion fiber laser featuring large-mode-area photonic crystal fibers. After external compression, 550 fs pulses with 1.2 MW peak power are ... -
Generation of soliton molecules with independently evolving phase in a mode-locked fiber laser
Ortaç, Bülend; Zaviyalov, A.; Nielsen, C.K.; Egorov, O.; Iliew, R.; Limpert, J.; Lederer, F.; Tünnermann, A. (Optical Society of America, 2010)We report the experimental generation of two-soliton molecules in an ytterbium-doped fiber laser. These molecules exhibit an independently evolving phase and are characterized by a regular spectral modulation pattern with ... -
Geometric parametric instability of femtosecond pulses in graded-index multimode fiber
Teğin, Ugur; Ortaç, Bülend (Optical Society of America, 2017)We numerically and experimentally study the spatio-temporal femtosecond pulse evolution in graded-index multimode fiber at normal dispersion regime. We report the first demonstration of geometric parametric instability ... -
High power supercontinuum generation in graded-index multimode fibers
Teğin, Uğur; Ortaç, Bülend (Institute of Electrical and Electronics Engineers Inc., 2019)Over the years, supercontinuum generation in fibers are studied extensively. Photonic crystal fiber technology detailed these studies by allowing the change of dispersion parameter. Nowadays, multimode fibers attracted ... -
Integration of glass micropipettes with a 3D printed aligner for microfluidic flow cytometer
Bayram, A.; Serhatlıoğlu, Murat; Ortaç, Bülend; Demic, S.; Elbüken, Çağlar; Sen, M.; Solmaz, M. E. (Elsevier B.V., 2018)In this study, a facile strategy for fabricating a microfluidic flow cytometer using two glass micropipettes with different sizes and a 3D printed millifluidic aligner was presented. Particle confinement was achieved by ... -
Laser material processing lead to nanotoxicity
Kurşungöz, Canan; Taş, Sadık Taşkın; Alten, Barış; Yeşiltepe, Metin; Sara, M. Yıldırım; Sargon, Mustafa F.; Ortaç, Bülend (IEEE, 2017)[No abstract available]