Researchgate profile<\/a><\/p>\n Google scholar profile<\/a><\/p>\n Orcid #: 0000-0002-8819-4916<\/a><\/p>\n [25] Yusuf Aslan, Esma Derin, Kutay Sagdic, Timuc\u0327in Emre Tabaru, Ali Karatutlu<\/strong>, Bu\u0308lend Ortac\u0327, and Fatih Inci<\/p>\n Spatiotemporal Confinements of Distance-Dependent Emitters for Enhancing Plasmonic Signals\u00a0<\/a><\/p>\n ACS Appl. Mater. Interfaces<\/i><\/span> 2026 Vol 18\/Issue 7 doi: 10.1021\/acsami.5c24749<\/span><\/p>\n [24] Ali Karatutlu<\/strong><\/p>\n Amorphous Germanium Thin Films on Kapton Tape Fabricated Using Electron Beam Evaporation as Flexible \u03b3-Ray Radiation Monitoring Materials<\/a><\/p>\n Phys. Status Solidi RRL<\/i>,\u00a02025<\/span>,\u00a0000<\/span>, e202500289,\u00a0https:\/\/doi.org\/10.1002\/pssr.202500289<\/a>.<\/p>\n [23] <\/strong>Murat M\u0131s\u0131r, Saliha Mutlu, Servin Bagheralmoosavi, B\u00fclend Orta\u00e7, Ali Karatutlu<\/strong>, G\u00fcrkan Ye\u015fil\u00f6z, Sevil Savaskan Y\u0131lmaz<\/p>\n Synthesis and Characterization of Py(PCL), Py(PLLA) \u00a0Homopolymers, and Py(PCL-b-PLLA) Copolymers via Ring-Opening Polymerization: Determination of Structural, Optical, and Biocompatible Properties<\/a><\/p>\n Adv. Mater. Interfaces<\/i>\u00a012<\/span>, no.\u00a019<\/span>\u00a0(2025<\/span>): e00195.\u00a0https:\/\/doi.org\/10.1002\/admi.202500195<\/a><\/p>\n [22] <\/strong>Saliha Mutlu,\u00a0B\u00fclend Orta\u00e7, Ali Karatutlu<\/strong>, Taylan G\u00f6rkan, Engin Durgun, Dilek Soyler, Saniye Soylemez, Nergis Arsu, Sevil Savaskan Y\u0131lmaz<\/p>\n \u00a0Engineering of the high-power laser-induced synthesis of Ni-based metal-organic framework: Investigation of its optical properties, computational methodology, electrocatalytic performances and glucose-sensing ability<\/a><\/strong><\/p>\n Advanced Materials Technologies (2024) DOI: 10.1002\/admt.202401245<\/p>\n [21] <\/strong>Timu\u00e7in Emre Tabaru, Ali Karatutlu, <\/strong> and B\u00fclend Orta\u00e7<\/p>\n Phase-Shifted Bragg-Grating Consisting of Silicon Oxynitride Doped Silicon and Silica Alternating Layers Lab-on-Fiber for Biosensors with Ultrahigh Sensitivity and Ultra-Low Detection Limit<\/em> <\/a>2023, Optics & Lasers Technology DOI: 10.1016\/j.optlastec.2023.109693<\/span><\/a><\/p>\n [20] Ali Karatutlu, <\/strong>Timu\u00e7in Emre Tabaru, and B\u00fclend Orta\u00e7<\/p>\n Low-temperature synthesis of Silicon Oxynitride-doped Si for tunable Bragg gratings homogeneously deposited on Si, SiO2 and borosilicate substrates and the tip of SM and PM optical fibers, <\/a>2023, Advanced Optical Materials DOI: 10.1002\/adom.202300094<\/p>\n [19] <\/strong>Esra Kendir Tekgul, Yakup Midilli, Huseyin Can \u00c7ami\u00e7i, Elif Yapar Y\u0131ld\u0131r\u0131m, Ali Karatutlu<\/strong> and B\u00fclend Orta\u00e7 Effects of Gamma Radiation on Yb-doped Al-P-Silicate Optical Fibers<\/a><\/strong>\u00a0 Applied Physics B: Lasers and Optics 128,\u00a0<\/strong>170 (2022) DOI: 10.1007\/s00340-022-07891-y<\/p>\n [18] Ali Karatutlu, <\/strong>Elif Yapar Y\u0131ld\u0131r\u0131m, Esra Kendir, Yakup Midilli, Samet Ak\u00e7imen,\u00a0B\u00fclend Orta\u00e7 Fabrication of Biaxial Polarization-Maintaining Optical Fiber with Ultra-Low Bending-Dependent Polarization Extinction Ratio Deterioration<\/a>\u00a0 Optical Fiber Technology <\/strong>Volume 69, March 2022, 1028362022 DOI: 10.1016\/j.yofte.2022.102836<\/p>\n [17]<\/strong> \u0130. Seker, A. Karatutlu<\/strong>, K Golcuk, M. Karakiz, B. Orta\u00e7,A Systematic Study on Au-capped Si Nanowhiskers for Size-Dependent Improved Biosensing Applications,<\/a> Plasmonics<\/strong>, 15:1739\u20131745 (2020) DOI: 10.1007\/s11468-020-01195-7<\/p>\n [16]<\/strong> A. Karatutlu, <\/strong>Atomic layer deposition of zirconium oxide thin film on an optical fiber for cladding light strippers, <\/a>Turkish Journal of Physics<\/strong>, DOI: 10.3906\/fiz-1908-6<\/a>, Available online: 07.01.2020<\/p>\n [15]<\/strong> E. Y. Y\u0131ld\u0131r\u0131m, A. Karatutlu<\/strong>, E. T. Balk, Y. Midilli, B. Orta\u00e7 Combined method for the fabrication of high-power cladding light stripper using buffered oxide etchant\u00a0 <\/a>Applied Optics<\/strong>,\u00a0Vol. 58, Issue 25,pp. 6926-6933(2019) Click here to read more<\/span><\/a><\/p>\n Cladding light strippers 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 cladding light stripper(CLS) device using a buffered oxide etchant by a combined method of stain (wet) etching and vapor phase etching.This high-power CLS was shown to result in a stripping performance of ~17.2 dB at the launched power of 333 W(pump limited).<\/p>\n [14] <\/strong>C. Candan, A. A. Seymen, A. Karatutlu<\/strong>, M. Tiken, Y. Midilli, ,E. Orhan, H. Berbero\u011flu, B. Orta\u00e7 Performance Evaluation of Fiber-based Ballistic Composites against Laser Threats<\/a>,<\/span><\/span> Optics and Lasers in Engineering<\/span><\/span><\/span><\/strong> Volume 121, October 2019, Pages 54-60 Click doi: 10.1016\/j.optlaseng.2019.03.016<\/a><\/p>\n In this study, a specially developed composite material for the ballistic applications was shined to a continuous wave (CW) laser beam at 915\u202fnm. At the instant of the exposure, the region of interest was completely evaporated and punctured with a slight swelling around the hole where the temperature was over 450 \u00b0C. The composite material was drilled completely upon exceeding 20\u202fkJ of laser energy.<\/p>\n [13] A. Karatutlu<\/strong>, F. S. Boi, R. Wilson, O. Ersoy, B. Orta\u00e7 , A. Sapelkin A Bean-like Formation of Nanoparticles inside the Carbon Nanotubes: Colloidal Germanium Nanoparticles Implanted throughout Iron-filled CNTs <\/a><\/span>\u00a0Crystal Research & Technology <\/strong>2018-10-22 [12] A Karatutlu<\/strong>, \u00a0B Patil, \u2026, A. Sapelkin Structural, Optical, Electrical and Electrocatalytic Activity Properties Of Luminescent Organic Carbon Quantum Dots<\/strong><\/span> 3<\/strong>\/17 2018 Chemistry Select<\/strong> Click doi: 10.1002\/slct.201800714<\/a><\/p>\n [11]<\/strong> \u015eeker, \u0130., Karatutlu, A.<\/strong> & \u0130stengir, S. Preferential MBE Growth and Characterization of SiGe Nanoislands on Depth-Selective Si Pits Etched by Ar + Plasma<\/strong><\/span>. Phys. status solidi – Rapid Res. Lett. <\/strong>1700424 (2018). doi:10.1002\/pssr.201700424<\/a><\/p>\n Preferential deposition of SiGe nanoislands<\/strong> is selectively<\/strong> demonstrated inside Si nanopits<\/strong> depending on the pit depth. Surface migration plays a role in the deposited Si pits where the selective behavior is surpassed and the SiGe nanoislands are grown all along the Si surface. Such an approach obtained in an MBE system gives the advantage of preparation of different depths and coating thicknesses in situ. <\/span><\/p>\n [10<\/strong>] I Seker, A. Karatutlu<\/strong>, O Gurbuz, S Yanik, Y Bakis, M Karakiz (2018) Structural and electrical investigations of MBE-grown SiGe nanoislands<\/strong><\/span> App. Phys. A Materials Science & Eng.<\/strong> DOI: 10.1007\/s00339-017-1448-6<\/a><\/p>\n SiGe nanoislands were grown by Molecular Beam Epitaxy (MBE) method on Si (100) substrates with comparative growth parameters<\/strong> such as annealing temperature, top Ge content and layer-by-layer annealing (LBLA).<\/p>\n [9] Karatutlu A<\/strong>, Istengir S, Cosgun S, Seker I, Unal B. Decalin-assisted light emitting porous Si formation and its optical, surface and morphological properties.<\/strong><\/span> Appl Surf Sci<\/em><\/strong> 2017;422:498\u2013503. doi:10.1016\/j.apsusc.2017.06.057<\/a>.<\/p>\n We report the optimum conditions for production of the most efficient Lep-Si<\/strong> using decalin (decahydronaphtalene) and possible structural origins of light emission using the depth dependent luminescence measurements.<\/p>\n [8]<\/strong> M. Song, A. Karatutlu<\/strong>, I. Ali, O. Ersoy, Y. Zhou, Y. Yang, Y. Zhang, W. R. Little, A. P. Wheeler, and A. V. Sapelkin, \u201c\u00c7ok k\u00fc\u00e7\u00fck Ge kuantum noktac\u0131klar\u0131 kullanarak, spektroskopik s\u00fcper \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc h\u00fccre g\u00f6r\u00fcnt\u00fclemesi ger\u00e7ekle\u015ftirilmi\u015ftir.<\/strong><\/span>\u201d Opt. Express<\/em><\/strong>, vol. 25, no. 4, p. 4240, Feb. 2017. DOI: 10.1364\/OE.25.004240<\/a><\/p>\n We demonstrate a spectroscopic imaging based super-resolution approach by separating the overlapping diffraction spots<\/strong> into several detectors during a single scanning period and taking advantage of the size-dependent emission wavelength in nanoparticles. This approach has been tested using off-the-shelf quantum dots (Invitrogen Qdot) and in-house novel ultra-small (~3 nm) Ge QDs.<\/p>\n [7]<\/strong> Zhang, Y., Ersoy, O., Karatutlu, A<\/strong>. & Sapelkin, A. (2016) Local structure of amorphous and nanoscale systems by numerical XANES calculations.<\/strong><\/span> Journal of Non-Crystalline Solids<\/em><\/strong>. 1\u20136. Click doi:10.1016\/j.jnoncrysol.2016.07.001<\/a>.<\/p>\n [6] Ali Karatutlu,<\/strong> Osman Ersoy, Willim R. Little, Yuanpeng Zhang, Isa Seker\u00a0 and\u00a0 Andrei Sapelkin:\u00a0 Laser-induced particle size tunes and structural transformations in germanium nanoparticles prepared by stain etching and colloidal synthesis route.<\/strong><\/span> Journal of Applied Physics<\/strong> 2015<\/strong> 118 (24), 244303 Click doi:10.1063\/1.4939066<\/a><\/p>\n [5]<\/strong> Yuanpeng Zhang, Osman Ersoy, Ali Karatutlu<\/strong>, Andrei Sapelkin: The local structure of Ge quantum dots determined by combined numerical analysis of extended x-ray absorption fine structure and x-ray absorption near-edge structure data.<\/span><\/strong> Journal of Synchrotron Radiation 10\/2015<\/strong>; 23 (1) Click doi:10.1107\/S160057751501913X<\/a><\/p>\n The sensitivity of X-ray absorption near-edge structure (XANES) to the local symmetry has been investigated in small ( [4]<\/strong> Niccolo R. C. Corsini, Yuanpeng Zhang, William R Little, Ali Karatutlu<\/strong>, Osman Ersoy, Peter D Haynes, Carla Molteni, Nicholas D M Hine, Jesus Gonzalez, Ignacio Hernandez, Fernando Rodriguez, Vadim V Brazhkin, Andrei V Sapelkin: Pressure-Induced Amorphization and a New High Density Amorphous Metallic Phase in Matrix-Free Ge Nanoparticles.<\/span><\/strong><\/em> Nano Letters 10\/2015<\/strong>; Click doi:10.1021\/acs.nanolett.5b02627<\/a><\/p>\n Here, we report on the remarkable behavior of small (under \u223c5 nm) matrix-free Ge nanoparticles under hydrostatic compression that is drastically different from both larger nanoparticles and bulk Ge.<\/strong> We discover that the application of pressure drives surface-induced amorphization leading to Ge\u2013Ge bond overcompression and eventually to a polyamorphic semiconductor-to-metal transformation.<\/p>\n [3]<\/strong> Ali Karatutlu<\/strong>, Mingying Song, Ann P. Wheeler, Osman Ersoy, William R. Little, Yuanpeng Zhang, Pascal Puech, Filippo S. Boi, Zofia Luklinska, Andrei V. Sapelkin: Synthesis and structure of free-standing Germanium quantum dots and their application in live cell imaging<\/em>.<\/span> RSC Advances<\/strong> 02\/2015<\/strong>; 5(26-26):20566-20573. Click doi:10.1039\/c5ra01529d<\/a><\/p>\n The structure of the as-prepared Ge quantum dots that were found is best described by a core\u2013shell model<\/strong> with a small crystalline core and an amorphous outer shell with a surface that was terminated by hydrogen-related species. Investigation of toxicity, based on a viability test, of as-prepared uncoated Ge quantum dots in HeLa cells was carried out and compared with the commercial carboxyl coated CdSe\/ZnSe quantum dots. The viability tests show that Ge quantum dots are less toxic when compared to commercial carboxyl coated CdSe\/ZnS quantum dots.<\/p>\n [2]<\/strong> Yuanpeng Zhang, Ali <\/strong>Karatutlu<\/strong>, Osman Ersoy, William Little, Giannantonio Cibin, Andy Dent, Andrei Sapelkin: Structure and effects of annealing in colloidal matrix-free Ge quantum dots<\/em>. <\/span>Journal of Synchrotron Radiation 01\/2015<\/strong>; 22(1-1):105-112. Click doi:10.1107\/S1600577514022486<\/a><\/p>\n It was found that as-prepared samples possess distinctly different structures depending on their synthesis route<\/strong> as indicated by their long-range ordering.<\/strong> An appreciable amount of oxygen was found to be bound to Ge in samples prepared with GeO2<\/sub><\/span> as a precursor; however, not for GeCl4<\/sub><\/span>.Annealing in an H2<\/sub><\/span>Ar atmosphere leads to sample crystallization and further nanoparticle growth, while at the same time reducing the Ge-O bonding.<\/p>\nOrijinal Ara\u015ft\u0131rma Makaleleri<\/span><\/h1>\n
2026<\/span><\/h2>\n
2025<\/span><\/h2>\n
2024<\/span><\/h2>\n
2023<\/span><\/h2>\n
2022<\/span><\/h2>\n
2020<\/span><\/h2>\n
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<\/div>\n2019<\/span><\/h2>\n<\/div>\n<\/div>\n
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<\/a>A recipe for a junction of Ge\/Fe inside a single CNT<\/b> is demonstrated with a bean\u2010like deposition of Ge NPs. The results indicate that Ge NPs and IF\u2010CNTs demonstrate cocatalytic activity in increasing the respective sizes, which are dramatically larger than those obtained by the conventional approaches.<\/span><\/p>\n![\"\"](\"http:\/\/drkaratutlu.com\/wp-content\/uploads\/2018\/10\/TOC-graphic-300x169.png\")
<\/a>We demonstrate organic carbon quantum dots (qdots) containing nitrile bonded (C\u2261N bond) d\u2010glucos<\/i>e\u2010like traces<\/strong> in various sizes obtained from wheat flour to be promising for imaging applications and to possess a relaxor ferroelectric property and an enhanced electrocatalytic activity that could reduce the cost of energy devices and simple to scale up for the commercialization.<\/p>\n![](\"https:\/\/wol-prod-cdn.literatumonline.com\/cms\/attachment\/eee00754-34d8-4b85-b44e-0c2523df8271\/pssr201700424-blkfxd-0001-m.jpg\")
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<\/p>\n2017<\/span><\/h2>\n
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2016<\/span><\/h2>\n
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<\/a>We reproduce the key spectral features in XANES calculations of Ge nanoparticles using the final difference method of FDMNES code.<\/strong> We suggest ways of resolving remaining outstanding issues arising from combination of disorder, size and surface effects.<\/p>\n2015<\/span><\/h2>\n
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<\/a>Systematic studies of the laser exposure on Ge nanoparticles prepared by colloidal synthesis results in the fact that the explosive crystallisation<\/strong> is common for H-terminated and partially disordered Ge nanoparticles regardless of its particle size. We suggest possible bio-medical applications for the observed phenomena.<\/p>\n![\"\"](\"http:\/\/drkaratutlu.com\/wp-content\/uploads\/2018\/10\/JSR1.png\")
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4\u00a0nm) matrix-free Ge quantum dots.<\/strong> The FDMNES<\/i><\/span> package was used to calculate the theoretical XANES spectra that were compared with the experimental data of as-prepared and annealed nanoparticles.<\/p>\n![](\"https:\/\/pubs.acs.org\/na101\/home\/literatum\/publisher\/achs\/journals\/content\/nalefd\/2015\/nalefd.2015.15.issue-11\/acs.nanolett.5b02627\/20151105\/images\/medium\/nl-2015-026272_0006.gif\")
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