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dc.contributor.advisorİlday, Fatih Ömeren_US
dc.contributor.authorKesim, Denizhan Korayen_US
dc.date.accessioned2019-04-24T05:55:16Z
dc.date.available2019-04-24T05:55:16Z
dc.date.copyright2019-03
dc.date.issued2019-04
dc.date.submitted2019-04-22
dc.identifier.urihttp://hdl.handle.net/11693/50912
dc.descriptionCataloged from PDF version of article.en_US
dc.descriptionThesis (Ph.D.): Bilkent University, Department of Electrical and Electronics Engineering, İhsan Doğramacı Bilkent University, 2019.en_US
dc.descriptionIncludes bibliographical references (leaves 58-63).en_US
dc.description.abstractAblation cooled material removal opened up great opportunities for understanding nonlinear processes. Especially using lasers as a tool to tailor nonlinear temperature gradient of material and engineering them to achieve effects such as high ablation efficiency, speed, and low collateral damage. Numerical simulations showed such engineering of the temperature gradient of material is possible for any repetition rate falling inside the ablation cooling regime. Two temperature model is used to investigate the effects of repetition rate, pulse energy, and burst duration. Simulations suggest ablation can continue indefinitely as burst duration increases. They also suggest there is an optimum pulse energy for any repetition rate in terms of efficiency of ablation regarding the material. The results of the simulations are confirmed by experiments using lasers with 1.6 GHz, 1.46 GHz, and 13 GHz repetition rate on biological and technical materials. The ablation threshold for a single pulse is lowered 100 times compared to our previous publication. Finally, related studies that can build upon the shown results are presented. A new thin-disk laser oscillator scheme is proposed that implements mode-locking regimes already established in fiber lasers. Dissipative soliton and similariton simulation results are promising for further studies. They can achieve high energy pulses with the help of nonlinear effects instead of limited by it. Then, a new computer generated hologram algorithm is explained where hundreds of layers can be generated from a single hologram. The algorithm utilizes diffusion as a tool to increase the degree of freedom which in turn decreases the cross-talk between layers.en_US
dc.description.statementofresponsibilityby Denizhan Koray Kesimen_US
dc.format.extentxii, 77 leaves : illustrations, charts ; 29 cm.en_US
dc.language.isoEnglishen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectBurst modeen_US
dc.subjectLaser material processingen_US
dc.subjectAblation coolingen_US
dc.subjectUltrashort pulsesen_US
dc.subjectNonlinear systemen_US
dc.subjectThermal profileen_US
dc.titleTailoring nonlinear temperature profile in laser-material processingen_US
dc.title.alternativeDoğrusal olmayan sıcaklık profilinin lazer materyal işleme için düzenlenmesien_US
dc.typeThesisen_US
dc.departmentDepartment of Electrical and Electronics Engineeringen_US
dc.publisherBilkent Universityen_US
dc.description.degreePh.D.en_US
dc.identifier.itemidB155919
dc.embargo.release2019-10-22


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