Advisory Committee Chair
Renato P Camata
Document Type
Dissertation
Date of Award
2010
Degree Name by School
Doctor of Philosophy (PhD) College of Arts and Sciences
Abstract
Transition metal doped II-VI semiconductor materials features excellent spectroscopic and lasing characteristics in the middle infrared (mid-IR). Among this class of laser material, the most impressive results have been obtained from chromium-doped zinc selenide (Cr2+:ZnSe) crystals. To date, Cr2+:ZnSe materials are arguably the best choice of laser gain material for the advancements of high power mid-IR lasers broadly tunable over the 2-3 μm spectral range. The dissertation objectives are to demonstrate technological advancements in the development Cr2+:ZnSe thin films by pulsed laser deposition (PLD) thus establishing a viable route for the synthesis of mid-IR laser gain media based on Cr2+:ZnSe thin films. The first major objective of this dissertation is the realization of high optical quality Cr2+:ZnSe thin films with effective control over the Cr2+ dopant concentration and uniformity. Accomplishing this objective could only be attained through the availability of high quality Cr-doped ZnSe ablation targets. Manufacturing procedures for ablation targets fabricated in-house were perfected and used to produce Cr2+ concentration variations in films deposited to less than 15% in samples with Cr2+ concentration ~1019 ions/cm3. PLD deposition parameters were optimized that resulted in formation of high optical quality Cr2+:ZnSe films that were used to consistently exhibit room temperature photoluminescence (PL) measurements over the 2-3 μm mid-IR spectral range. This was the first demonstration of PL measurements from PLD grown Cr2+:ZnSe thin films. The second objective was to demonstrate mid-IR lasing from PLD grown Cr2+:ZnSe based thin film structures. The first demonstration of 2.63 μm mid-IR lasing in a Cr2+:ZnSe thin film planar waveguide structure developed using PLD is presented in this dissertation research. Mid-IR lasing oscillation within a planar waveguide, achieved through the deposition of a highly doped Cr2+:ZnSe film on sapphire substrate, was obtained at room temperature under gain-switched optical excitation. Highly doped Cr2+:ZnSe thin films were also used to demonstrate passive Q-switching of Er-doped YAG laser operating at 1.645 μm. The third objective was to develop Cr2+:ZnSe-based thin film electroluminescent structures by PLD. Significant progress was made in the development of thin film structure designs that shows promising results for the impending successful demonstration of mid-IR electroluminescence.
Recommended Citation
Williams, Jonathan Ezekiel, "Growth of Chromium-Doped Zinc Selenide Thin Films by Pulsed Laser Deposition for Mid-Infrared Applications" (2010). All ETDs from UAB. 3330.
https://digitalcommons.library.uab.edu/etd-collection/3330
