| Title |
Fabrication and Characterization of Low-dimensional Nanomaterial Saturable Absorbers for Mode-locking of Fiber Lasers / |
| Translation of Title |
Nanostruktūrinių darinių, skirtų skaidulinių lazerių modų sinchronizacijai, formavimas ir pritaikymas, eliminuojant laisvos erdvės elementus. |
| Authors |
Viskontas, Karolis |
| Full Text |
|
| Pages |
39 |
| Keywords [eng] |
mode-locked fiber laser ; saturable absorber ; SESAM ; carbon nanotubes ; Ytterbium-doped gain medium |
| Abstract [eng] |
This doctoral thesis contains the results from experiments with nonlinear low dimensionality nanomaterials in order to fabricate the saturable absorber for mode-locking of fiber laser. The research work was important for developing a reliable picosecond pulse source for scientific and industrial laser systems. To achieve these objectives the all-fiber experimental setups for measuring the nonlinear optical properties and carrier relaxation characteristics of saturable absorber were introduced. With these techniques it was possible to monitor both short-term and long-term changes in the optical properties of the absorber. Major part of the dissertation was dedicated to the study of semiconductor InGaAs quantum well (2D) saturable absorber mirrors (SESAMs) and determination of optimal nonlinear parameters in order to ensure a reliable and long-term performance of single-mode pulsed ytterbium doped fiber laser. The presented data on SESAM degradation and mechanisms influencing it revealed that the nature of the optical modification strongly depends on the saturation parameter of absorber and therefore the accelerated damage tests do not predict the lifetime of a SESAM. Also, the fabrication of low saturation fluence SESAM was introduced and implantation of heavy (As) and light (H) ions into the semiconductor structure was described in detail. The nonlinear optical properties of alternative single wall carbon nanotube (1D) saturable absorbers were investigated. Also, the integration of one dimensional material into the ytterbium and thulium/holmium fiber laser resonators was realized. It was shown that, in order to use them for a specific wavelength fiber laser, it is necessary to choose an appropriate diameter of the carbon nanotube. Further, the suitability of other low dimensional structures (lead selenide quantum dots and silver nanoprisms) for mode-locking of fiber laser was evaluated. |
| Dissertation Institution |
Vilniaus universitetas. |
| Type |
Summaries of doctoral thesis |
| Language |
English |
| Publication date |
2016 |
