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Atomic, Molecular and Optical Physics

University of New Mexico

2020

Articles 1 - 6 of 6

Full-Text Articles in Physics

Radial Basis Densities And The Density Functional-Based Atom-In-Molecule: Designing Charge-Transfer Potentials, Godwin Amo-Kwao Nov 2020

Radial Basis Densities And The Density Functional-Based Atom-In-Molecule: Designing Charge-Transfer Potentials, Godwin Amo-Kwao

Nanoscience and Microsystems ETDs

Classical potentials that are capable of describing charge transfer and charge polarization in complex systems are of central importance for classical atomistic simulation of biomolecules and materials. Current potentials—regardless of the system—do not generalize well, and, with the exception of highly-specialized empirical potentials tuned for specific systems, cannot describe chemical bond formation and breaking. The charge-transfer embedded atom method (CT-EAM), a formal, DFT-based extension to the original EAM for metals, has been developed to address these issues by modeling charge distortion and charge transfer in interacting systems using pseudoatom building blocks instead of the electron densities of isolated atoms. CT-EAM …

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Generation Of Correlated Dual Frequency Combs With Pm Fiber Lasers For High-Precision Metrology, Hanieh Afkhamiardakani Jul 2020

Generation Of Correlated Dual Frequency Combs With Pm Fiber Lasers For High-Precision Metrology, Hanieh Afkhamiardakani

Optical Science and Engineering ETDs

Intracavity Phase Interferometry (IPI) using two correlated, counter-propagating frequency combs (pulse trains) in mode-locked lasers has evolved into a powerful technique for high-precision metrology. In this method a physical parameter to be measured imparts a phase shift onto a pulse circulating in the laser cavity. Inside a laser cavity, that phase shift becomes a frequency shift (phase shift/round-trip time) applied to the whole frequency comb created by this pulse as it exits the cavity at each round-trip. This frequency shift is measured by interfering this comb with a reference comb created by a reference pulse circulating in the same mode-locked …

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Radiation-Balanced Fiber Lasers And Amplifiers, Esmaeil Mobini Souchelmaei Mr Jul 2020

Radiation-Balanced Fiber Lasers And Amplifiers, Esmaeil Mobini Souchelmaei Mr

Optical Science and Engineering ETDs

Over the past decades, high-power fiber lasers and amplifiers have been extensively under research to achieve higher output powers. However, temperature rise in the core of fiber lasers and amplifiers has been a big issue in power-scaling. Radiation-balancing is a viable technique introduced for effective heat mitigation in lasers and amplifiers by S. Bowman in 1995. Radiation-balancing relies on solid-state laser cooling as a self-cooling mechanism to mitigate the generated heat in lasers and amplifiers. To implement the mentioned idea in fiber lasers and amplifiers, a set of issues should be scrutinized; (i) the amenability of silica glass (as the …

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Applications Of The Negatively-Charged Silicon Vacancy Color Center In Diamond, Forrest A. Hubert Apr 2020

Applications Of The Negatively-Charged Silicon Vacancy Color Center In Diamond, Forrest A. Hubert

Optical Science and Engineering ETDs

The spatial resolution and fluorescence signal amplitude in stimulated emission depletion (STED) microscopy is limited by the photostability of available fluorophores. Here, we show that negatively-charged silicon vacancy (SiV) centers in diamond are promising fluorophores for STED microscopy, owing to their photostable, near-infrared emission and favorable photophysical properties. A home-built pulsed STED microscope was used to image shallow implanted SiV centers in bulk diamond at room temperature. We performed STED microscopy on isolated SiV centers and observed a lateral full-width-at-half-maximum spot size of 89 ± 2 nm, limited by the low available STED laser pulse energy (0.4 nJ). For a …

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Mid-Ir Optical Refrigeration And Radiation Balanced Lasers, Saeid Rostami Apr 2020

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 …

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A Short Remark On Vortex As Fluid Particle From Neutrosophic Logic Perspective, Victor Christianto, Florentin Smarandache Jan 2020

A Short Remark On Vortex As Fluid Particle From Neutrosophic Logic Perspective, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In a previous paper in this journal (IJNS), it is mentioned about a possible approach to re-describe QED without renormalization route. As it is known that in literature, there are some attempts to reconcile vortex-based fluid dynamics and particle dynamics. Some attempts are not quite as fruitful as others. As a follow up to previous paper, the present paper will discuss two theorems for developing unification theories, and then point out some new proposals including by Simula (2020) on how to derive Maxwell equations in superfluid dynamics setting; this could be a new alternative approach towards “fluidicle” or “vorticle” model …

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