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High-Power Laser Cooling And Temperature-Dependent Fluorescence Studies Of Ytterbium Doped Silica, Brian Topper
High-Power Laser Cooling And Temperature-Dependent Fluorescence Studies Of Ytterbium Doped Silica, Brian Topper
Optical Science and Engineering ETDs
Experimental observation of optical refrigeration using ytterbium doped silica glass in recent years has created a new solution for heat mitigation in high-power laser systems, nonlinear fiber experiments, integrated photonics, and precision metrology. Current efforts of different groups focus on compositional optimization, fiber fabrication, and investigating how much silica can be cooled with a laser. At the start of this work, the best effort in laser cooling ytterbium doped silica saw cooling by 6 K from room temperature. This dissertation follows the experimental efforts that culminated in the increase of this initial record by one order of magnitude. Comprehensive spectroscopic …
Mid-Ir Optical Refrigeration And Radiation Balanced Lasers, Saeid Rostami
Mid-Ir Optical Refrigeration And Radiation Balanced Lasers, Saeid Rostami
Optical Science and Engineering ETDs
This dissertation reports recent advances in mid-infrared (mid-IR) optical refrigeration and Radiation Balanced Lasers (RBLs). The first demonstration of optical refrigeration in Ho:YLF and Tm:YLF crystals as promising mid-IR laser cooling candidates is reported. Room temperature laser cooling efficiency of Tm- and Ho-doped crystals at different excitation polarization is measured and their external quantum efficiency and background absorption are extracted. Complete characterization of laser cooling samples is obtained via performing detailed low-temperature spectroscopic analysis, and their minimum achievable temperature as well as conditions to achieve laser cooling efficiency enhancement in mid-IR are investigated. By developing a Thulium-doped fiber amplifier, seeded …