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Articles 1 - 8 of 8
Full-Text Articles in Physics
Numerical Simulation Of Unstable Laser Resonators With A High Gain Medium, Robert L. Lloyd
Numerical Simulation Of Unstable Laser Resonators With A High Gain Medium, Robert L. Lloyd
Theses and Dissertations
This research focused on the numeric simulation of unstable laser resonators with high gain media. In order to accomplish the research, the modes and eigenvalues for various bare cavity resonator were computed followed by modes of a resonator in the presence of gain. Using a Fourier Split Step Method in a Fox and Li iteration scheme, different laser outputs for various laser cavities with gain were computed. Various parameters defining positive branch confocal unstable resonators were chosen corresponding to four studies. The four studies focused on modifying laser cavity Fresnel number, gain medium parameters, gain cell position, and gain cell …
Rbhe Potential Energy Surface Sensitivity Study, Ethan D. Thorp
Rbhe Potential Energy Surface Sensitivity Study, Ethan D. Thorp
Theses and Dissertations
This paper studies how alterations of features of RbHe potential energy surfaces (PES) for a diode pumped alkali laser (DPAL) system effect the collisional cross section. The Split-Operator method is used to propagate a wave function along these PES and because they are radially coupled, the wave function can be transmitted from the starting surface to other energy surfaces. This transmittance is encoded in the correlation function. The full Hamiltonian used for propagation consists of the electronic potential, the nuclear kinetic energy, and the Coriolis coupling. The correlation function is used to generate the Scattering Matrix elements. These elements describe …
High Pressure Line Shapes Of The Rb D1 And D2 Lines For 4He And 3He Collisions, Wooddy S. Miller, Christopher A. Rice, Gordon D. Hager, Matthew D. Rotondaro, Hamid Berriche, Glen P. Perram
High Pressure Line Shapes Of The Rb D1 And D2 Lines For 4He And 3He Collisions, Wooddy S. Miller, Christopher A. Rice, Gordon D. Hager, Matthew D. Rotondaro, Hamid Berriche, Glen P. Perram
Faculty Publications
Line shapes for the Rb D1 (52S1/2 ↔ 52P1/2) and D2 (52S1/2 ↔ 52P3/2) transitions with 4He and 3He collisions at pressures of 500–15,000 Torr and temperatures of 333–533 K have been experimentally observed and compared to predictions from the Anderson–Talman theory. The ground X2Σ+1/2 and excited A2Π1/2, A2Π3/2, and B2Σ+1/2 potential energy surfaces required for the line shape predictions have been calculated using a one-electron …
Temperature Dependent Rubidium-Helium Line Shapes And Fine Structure Mixing Rates, Wooddy S. Miller
Temperature Dependent Rubidium-Helium Line Shapes And Fine Structure Mixing Rates, Wooddy S. Miller
Theses and Dissertations
Diode Pumped Alkali Lasers (DPALs) are a new type of laser that uses alkali metal vapor as a gain medium and a buffer gas to control the line shape and kinetics. While these systems were first demonstrated in 2003 [48] they have just recently been scaled to the kilowatt power levels in 2012 [18]. To achieve these powers, the design of the gain cell relied on a set of incomplete line shape and kinetic data. The current focus areas of DPAL research are the continued power scaling of the systems and basic science research into the rates involved within the …
Scaling Of An Optically Pumped Mid-Infrared Rubidium Laser, Paul J. Moran
Scaling Of An Optically Pumped Mid-Infrared Rubidium Laser, Paul J. Moran
Theses and Dissertations
An optically pumped mid-infrared rubidium (Rb) pulsed laser has been demonstrated in a heat pipe along the 62P3/2 - 62S1/2 transition at 2.730 µm and the 62P1/2 - 62S1/2 transition at 2.790 µm. The bleached limit, slope efficiency, and maximum laser output energy of the mid-IR Rb laser have been shown to scale linearly with increasing Rb density, contrary to prior laser demonstrations. A maximum output energy of 5 nJ per pulse had previously been observed before a rollover occurred in the scaling of output energy with Rb …
Diffusion Of Rubidium Vapor Through Hollow-Core Fibers For Gas-Phase Fiber Lasers, Eric M. Guild
Diffusion Of Rubidium Vapor Through Hollow-Core Fibers For Gas-Phase Fiber Lasers, Eric M. Guild
Theses and Dissertations
This work examines the diffusion of rubidium through a small diameter tube alone and in the presence of noble gases. A fluid dynamics analysis is investigated to aid in choosing a method for transferring atomic rubidium vapor that is reliable and efficient. Solutions to the time dependant ordinary differential equation describing the experimental flow properties of the system reveal more precise outcomes than previously practiced routines. Resolved viscosities and Poiseuille flow theory velocity profile distributions are characterized for noble gas carriers of the rubidium vapor. Applying Reynolds Numbers to the flow experiments provides pressure differential boundaries that are employed in …
Hard Collisions In Rubidium Using Sub-Doppler Spectroscopy, Douglas E. Thornton
Hard Collisions In Rubidium Using Sub-Doppler Spectroscopy, Douglas E. Thornton
Theses and Dissertations
To better understand the laser kinetics of an alkali gain medium, hard collisions, or velocity-changing collisions, has been studied and a velocity-changing collisional rate has been calculated. Previous works have studied these collisions, but no rate has been calculated. Using the precise tool of sub-Doppler spectroscopy, atomic hard collisions can be observed. The collected spectra are fitted with two different line shapes to demonstrate the accuracy of this method. From the fits, the number of hard collisions can be extracted. The time scale of the hard collisions in rubidium is interpolated by varying the chopping frequency of the pump beam, …
Rubidium Recycling In A High Intensity Short Duration Pulsed Alkali Laser, Wooddy S. Miller
Rubidium Recycling In A High Intensity Short Duration Pulsed Alkali Laser, Wooddy S. Miller
Theses and Dissertations
Laser induced fluorescence was used to study how pump pulse duration and alkali recycle time effects maximum power output in a Diode Pumped Alkali Laser (DPAL) system. A high intensity short pulsed pump source was used to excited rubidium atoms inside a DPAL-type laser. The maximum output power of the laser showed a strong dependence upon the temporal width of the pump pulse in addition to the input pump intensity. A linear relationship was observed between the maximum output power and the pulse width due to the effective lifetime of the excited state, defined as the time it takes for …