Author
Zhu, GongwenIssue Date
2015Keywords
Fiber lasersMid-infrared lasers
Mode-locked lasers
Q-switched lasers
Raman lasers
Optical Sciences
Fiber amplifiers
Advisor
Peyghambarian, Nasser
Metadata
Show full item recordPublisher
The University of Arizona.Rights
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.Abstract
Mid-infrared (IR) lasers (2-12 μm) have found tremendous applications in medical surgeries, spectroscopy, remote sensing, etc. Nowadays, mid-IR emissions are usually generated from semiconductor lasers, gas lasers, and solid-state lasers based on nonlinear wavelength conversion. However, they usually have disadvantages including poor beam quality, low efficiency, and complicated configurations. Mid-IR fiber lasers have the advantages of excellent beam quality, high efficiency, inherent simplicity, compactness, and outstanding heat-dissipating capability, and have attracted significant interest in recent years. In this dissertation, I have studied and investigated Q-switched and mode-locked fiber lasers in the mid-IR wavelength region. My dissertation includes six chapters: In Chapter 1, I review the background of mid-IR lasers and address my motivation on the research of mid-IR fiber lasers; In Chapter 2, I present the experimental results of microsecond and nanosecond Er³⁺-doped and Ho³⁺-doped fiber lasers in the 3 μm wavelength region Q-switched by Fe²⁺:ZnSe and graphene saturable absorbers. In Chapter 3, Q-switched 3 μm laser fiber amplifiers are investigated experimentally and theoretically and their power scaling are discussed. In Chapter 4, a graphene mode-locked Er³⁺-doped fiber lasers at 2.8 μm with a pulse width < 50 ps is presented. In Chapter 5, extending the spectral range of mid-IR fiber lasers by use of nonlinear wavelength conversion is addressed and discussed. I have proposed 10-watt-level 3-5 μm Raman lasers using tellurite fibers as the nonlinear gain medium and pumped by our Er³⁺-doped fiber lasers at 2.8 μm. In the last chapter, the prospect of mid-IR fiber laser is addressed and further research work is discussed.Type
textElectronic Dissertation
Degree Name
Ph.D.Degree Level
doctoralDegree Program
Graduate CollegeOptical Sciences
Degree Grantor
University of ArizonaCollections
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