Condensed Matter Physics Commons^™

Investigating A Nanoparticle-Assisted Approach For Localized Strain Engineering In Two-Dimensional Materials, Skye Martichuski

Honors Theses and Capstones

This work investigated a fabrication strategy for inducing localized nanoscale deformation and strain in transferred MoS2 flakes using gold nanoparticle-coated substrates as a potential platform for strain engineering in two-dimensional materials. Substrate type, nanoparticle concentration, drying conditions, cleaning procedures, and flake transfer methods were investigated using optical microscopy and atomic force microscopy (AFM). Au-coated SiO2 substrates produced improved nanoparticle coverage compared to bare SiO2, while passive air drying yielded the most favorable nanoparticle distributions. Salt crystals introduced during passive drying were successfully removed with a gentle deionized water rinse, and a 50% diluted gold nanoparticle suspension provided improved particle spacing …

Quantum Critical Behavior Of Diluted Quasi-One-Dimensional Ising Chains, Logan Sowadski, Thomas Vojta

Physics Faculty Research & Creative Works

(Formula presented.) (Formula presented.) is a unique magnetic material. It features bulk 3D magnetic order at low temperatures, but its quantum critical behavior in a magnetic field is well described by the 1D transverse-field Ising universality class. This behavior is facilitated by the structural arrangement of magnetic (Formula presented.) ions in nearly isolated zig-zag chains. In this work, we investigate the effect of random site dilution on the critical properties of such a quasi-1D quantum Ising system. To this end, we introduce an anisotropic site-diluted 3D transverse-field Ising model. We find that site dilution leads to unconventional activated scaling behavior …

Investigating The Effects Of Pressure On Fe And Co Intercalated 2h-Tas2 Through First-Principle Calculations, Ronald E. Putnam Jr.

UNF Graduate Theses and Dissertations

Using first-principles methods, we investigate the effects of applied isotropic pressure on the electronic and magnetic properties of intercalated Fe1/3TaS2 and Co1/3TaS2. Fe1/3TaS2 has been shown to be a ferromagnet that undergoes structural and magnetic phase transitions under applied pressure. The magnetic phase transitions are observed to be linked to the structural shift, and a mixture of magnetic phase states is present between 3 GPa and 6 GPa. Co1/3TaS2 was found to be antiferromagnetic, as confirmed by experimental work. One- and two-unit-cell systems of Co1/3TaS2 are analyzed, both showing band splitting that disappears under pressure. The application of pressure forces …

First-Principles Investigation Of Quasi-One-Dimensional Van Der Waals Magnets For Advancing Low-Dimensional Spintronics, Alyssa Horne

Dissertations, Master's Theses and Master's Reports

Van der Waals (vdW) magnets have been of great interest for advancing low- dimensional spintronics. A notable example is the quasi-one-dimensional (Q1D) vdW CrSbSe₃, as it is composed of individual one-dimensional units that are held together by the vdW forces. Finding other Q1D vdW magnets that exhibit non-metallic behavior together with long range ferromagnetic ordering is critical in developing next generation spintronics. Here in, using first-principles density functional theory (DFT), we investigate the compositional effects on electronic and magnetic behavior of Cr_1–xMn_xSbSe₃ (x = 0, 0.5, 1). When 50% of Cr is replaced …

Growth And Dielectric Characterization Of Epitaxial Sr1-Xmgxtio3 Thin Films, Richard Badu

UNF Graduate Theses and Dissertations

Complex oxide materials with ferroelectric ground states remain promising candi dates for next-generation high-capacitance and nonlinear microelectronic applica tions. One of those materials is SrTiO3 (STO). However, STO is an incipient fer roelectric with anomalously high dielectric permittivity at low temperatures. STO crystals possess a highly polarizable lattice that is sensitive to even small amounts of impurities. Substituting Mg into the STO matrix is predicted to induce a corre lation between ferroelectric and relaxor behavior. In this thesis, we demonstrated the growth of a series of epitaxial STO and Sr1-xMgxTiO3 thin films using molec ular beam epitaxy. The surface evolution …

Ultrafast Vibrational Dynamics In Important Wide-Bandgap Semiconductors, Dielectrics And Energetic Materials, Dinusha Madushanka Senarathna

Open Access Dissertations

This dissertation applies time-resolved coherent anti-Stokes Raman scattering (tr-CARS), to measure ultrafast vibrational dynamics in technologically important solid-state and van der Waals molecular systems. The central goal is to use time-domain Raman methods to resolve mode-specific phonon and vibrational dephasing processes with high temporal precision, high spectral selectivity, and sufficient experimental flexibility to probe materials ranging from wide-bandgap semiconductors and oxide crystals to energetic molecular crystals. Across the work, I show that carefully designed tr-CARS measurements can access vibrational lifetimes from hundreds of femtoseconds to several picoseconds, enabling direct observation of decay pathways, relaxation mechanisms, and dispersion effects that shape …

Charge Transport Modeling Of Multifunctional Molecular Transistors, Romena Akter

Graduate Studies Theses and Dissertations 2026

Distinguishing between the current–voltage characteristic curves associated with different transport mechanisms in a molecular electronic device and an artifact arising from device-level disorder is a central challenge in the study of molecular electronics. Characterizing these mechanisms and connecting them qualitatively to molecular-level orbital alignment, electrode coupling, voltage division, energetic disorder, and reorganization energy requires not only experimental data but also a rigorous theoretical framework for extracting physically meaningful parameters from measured transfer characteristics. This dissertation addresses this challenge in Chapters 2, 3, and 4 by developing and applying four complementary transport models —Simmons tunneling, single-level Landauer, Marcus hopping, and McConnell …

Emergent Spin Fluctuation And Structural Metastability In Self-Intercalated Cr1+Xte2 Compounds, Clayton Conner, Ali Sarikhani, Theo Volz, Mathew Pollard, Mitchel Vaninger, Xiaoqing He, Steven Kelley, Jacob Cook, Avinash Sah, John Clark, Hunter Lucker, Cheng Zhang, Paul Miceli, Yew San Hor

Physics Faculty Research & Creative Works

Intercalated van der Waals (vdW) magnetic materials host unique magnetic properties due to the interplay of competing interlayer and intralayer exchange couplings, which depend on the intercalant concentration within the van der Waals gaps. Magnetic vdW compound chromium telluride, (Formula presented.), has demonstrated rich magnetic phases at various Cr concentrations, such as the coexistence of ferromagnetic and antiferromagnetic phases in (Formula presented.) (equivalently, (Formula presented.)). The compound is created by intercalating 0.25 Cr atom per unit cell within the van der Waals gaps of (Formula presented.). In this work, we report a notably increased Curie Temperature and an emergent in-plane …

Nanostructured Cathode Catalysts For Aem Electrolysis: From Catalyst Design To Degradation And Hydrogen Dynamics, Yamini Kumaran

Electronic Theses & Dissertations (2024 - present)

Anion exchange membrane water electrolysis (AEMWE) presents a promising pathway toward cost-effective and sustainable hydrogen production by integrating the chemical robustness of alkaline systems with the compact, zero-gap design of proton exchange membrane electrolyzers. However, the widespread implementation of AEMWE is limited by the availability of highly active and durable platinum-group-metal (PGM)-free catalysts and by an incomplete understanding of their degradation behavior under realistic operating conditions.

This dissertation focuses on the development, characterization, and mechanistic investigation of nanostructured MoNi₄–MoO₂-based electrodes for efficient and stable hydrogen generation under alkaline and membrane-integrated environments. MoNi₄–MoO₂ nanorods …

Harnessing Coherent-Wave Control For Sensing Applications In Scattering Media, Pablo Xavier Jara Palacios

Doctoral Dissertations

"Diffuse electromagnetic waves are widely used for non-invasive sensing and imaging in complex scattering media such as biological tissues. A fundamental limitation of such techniques is the scarcity of detected photons: as the source-detector separation increases to access deeper regions of the medium, the signal strength decays rapidly, leading to poor signal-to-noise ratio and limited sensitivity. This dissertation addresses this challenge through a combination of theory and computation.

We show that coherent control of the incident optical wavefront can compensate for the scarcity of detected photons that limits conventional diffuse optical imaging, typically performed in the near-infrared spectral region. By …

Computationally Efficient Methods For Calculation Of Light-Matter Interaction In Large Semiconductor Quantum Dots, Chandler Martin

Dissertations - ALL

Quantum dots are a class of materials in the nanometer scale that have unique optical and electronic properties due to the quantum confinement effect. Traditional electronic structure computational techniques used for calculating these properties fall to scalability issues as the size of the quantum dot increases, or introduce significant errors into the final result. This makes using computational methods to predict new materials, or verify properties of existing materials, challenging to use for experimental applications of quantum dots. This gap between experiment and computation is due to large basis sets, expensive integrals, and storage and manipulation of tensors that grow …

Impact Of Ethanol On The Evolution Of One-Step Synthesized Gold Nanoplates And Nanostars And Their Effects On Raman Signal Enhancement, Ananda Fania, Nonni Soraya Sambudi, Kirana Yuniati Putri, Yuliati Herbani, Affi Nur Hidayah

Makara Journal of Science

Gold nanoplates and nanostars were synthesized from a gold metal salt solution (HAuCl₄) using a one-step synthesis method of ultraviolet C (UVC) light irradiation. The gold salt solution was mixed with ethanol in 6 mL with the following ratios: (1.5:4.5, 3:3, and 4.5:1.5), and subsequently irradiated with UVC light. Changes in localized surface plasmon resonance (LSPR) shifts were observed in real time at 30-min intervals for 2 h. The synthesis process produces gold nanoplates. While gold nanostars were synthesized from a solution of gold salt combined with ethanol, ascorbic acid, and AgNO₃, maintaining a consistent ratio …

Assessment Of The Melt Quality Of A 30% Scrap Adc12 Aluminium Alloy Using The Inclusion And Fluidity Measurement Instrument (Ifmi) With Mullite Ceramic Filters, Gusti Ruri Ruri Lestari, Sandya Ananda Riswan, Muhammad Anis, Ahmad Ashari, Paramita Vidya Ayuningtyas, Bambang Suharno Prof, Donanta Dhaneswara

Journal of Materials Exploration and Findings

The increasing demand for sustainable practices in the metal casting industry has driven the use of recycled aluminum alloys such as ADC12. However, the addition of aluminum scrap tends to increase oxide inclusions, which reduce melt fluidity and compromise casting quality. This study utilizes the Inclusion and Fluidity Measurement Instrument (IFMI), equipped with mullite ceramic filters, to assess the melt quality of ADC12 aluminum alloy containing 30% scrap. Fluidity and inclusion characteristics were evaluated at five pouring temperatures (660°C, 680°C, 700°C, 720°C, and 740°C). The results show that fluidity increased with temperature, reaching a peak of 84.6 g·s⁻¹ at 740°C, …

Equipment Criticality Analysis To Determine Asset Integrity Management System Scheme In Supporting Production Optimization Scenarios In The Aeging Field, Donny Andryanto, Donanta Dhaneswara

Journal of Materials Exploration and Findings

This research investigates the production decline and cost increase in the X&Y oil and gas fields from 2022 to 2023. Production fell by 34%, while production costs per barrel rose by 79%. To address these issues, a series of optimization processes are proposed. These aim to restructure and enhance the production facilities to reduce current production costs. The optimizations include reducing pressure at the PPP Platform in 2024. Additional steps include shutting down CPP-ORF 14” pipelines and most processes at CPP 2 Platform by 2027 to convert it into an accommodation platform. Further, the plan involves optimizing the release of …

Morphological Test Of Areca Nut Fiber Ceramic Membrane Using Scanning Electron Microscopy Energy Dispersive X-Ray Mapping Spectroscopy, Amelia Marzain, Siti Umi Kalsum, Marhadi Marhadi, Ahmad Nabil Shahab

Journal of Materials Exploration and Findings

This study investigates the potential of ceramic membranes derived from areca nut fiber as a cost-effective and environmentally sustainable material for the removal of iron (Fe) and manganese (Mn) from groundwater. Two types of membranes were fabricated: one without activation and one chemically activated using 10% sodium hydroxide (NaOH). The morphological and elemental characteristics of both membranes were analyzed using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) mapping. The concentrations of Fe and Mn before and after treatment were measured using Atomic Absorption Spectroscopy (AAS). The NaOH-activated membrane exhibited a more porous surface structure and higher oxygen content, …

First-Principles Insights Into Binary Oxide Systems Under Extreme Pressure, Daniel Schacher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pressure is powerful tool by which one can manipulate the properties of materials. In this work we utilize pressure to explore binary oxide systems and characterize their structural and electronic properties. The observation of anomalous structural and electronic behavior in the rutile to CaCl2 phase transition in SnO2 led to the prediction that such behavior is inherent to all oxides experiencing such a phase transition sequence.[1] Here, the ultra-wide band gap semiconductor GeO2 is confirmed to exhibit anomalous behavior during the rutile to CaCl2 phase transition. A phase pure rutile GeO2 sample synthesized under high-pressure, high-temperature, conditions is probed using …

Ultrafast Dynamics Of Two-Dimensional Electron Systems, Randy Michael Sterbentz

UNLV Theses, Dissertations, Professional Papers, and Capstones

On-chip terahertz time-domain spectroscopy (THz-TDS) is a technique useful for measuring the ultrafast electrodynamics of two-dimensional (2D) electronic systems. Charge carrier collisions occur on the sub-picosecond time scale, and strongly correlated electron interactions (such as superconductivity) typically have energies on the order of milli-electron-volts. These phenomena fall within the terahertz bandwidth, which has historically been difficult to access. Commercial electronics operate with transistors capable of switching rates of around 100 GHz, while small band gap semiconductors (like InGaAs) can detect light down to 0.75 eV (180 THz). When combined with the difficulty of measuring 2D layered materials, with lateral sizes …

Analysis Of Leakage In Nearshore Pipelines Using Fitness For Service Method To Ensure Mechanical Integrity Based On Api-579 Level 3, Elriandri Elriandri, Dedi Priadi

Journal of Materials Exploration and Findings

The Fitness for Service (FFS) analysis is performed as a quantitative assessment to evaluate the integrity condition of a pipeline. Essentially, FFS assessment helps determine whether equipment components can operate safely despite existing deficiencies. This evaluation is carried out using the Finite Element Method (FEM). In the case of an underwater pipeline that experiences leak due to anchor pull at the flange connection, it undergoes plastic deformation and is lifted approximately 1 meter. As a mitigation step, inspection and repairs have been carried out by the company. Subsequently, modeling is performed to reconstruct the deformation process of the pipeline. Then, …

Plasma-Enhanced Carbon Nanomaterial Synthesis: A Pathway To Reducing Greenhouse Gasses And Carbon-Based Waste., Zane Ronau

Electronic Theses and Dissertations

This research leveraged incorporation of capacitively coupled radio frequency plasma into chemical vapor deposition (CVD) for a reduction in the temperature requirements [a reduction of energy barrier] needed for the conversion of methane (CH₄), carbon dioxide (CO₂), and various carbon-based-waste to produce value-added carbon nanomaterials. An array of catalysts and catalyst supports were employed to optimize the synthesis of graphitic carbon under various gas environments, temperatures and pressures. The nanomaterials synthesized after fine tuning the growth parameters included graphene, carbon nanotubes (CNT), carbon microtubes and carbon nanocages with a variety of properties. Raman Spectroscopy was used …

Optical, Mechanical, And Transport Characterization Of Two-Dimensional Magnetic Materials., Hiruni Weerahennedige

Electronic Theses and Dissertations

This work investigates the structural, magnetic, thermoelectric, and optoelectronic behavior of layered two-dimensional (2D) materials, with emphasis on Fe₃GeTe₂, Ni-substituted Fe₃GeTe₂ alloys, and GeSe. The study aims to clarify how dimensionality, alloying, and external perturbations influence charge transport, magnetic ordering, and light-matter interactions in van der Waals crystals. Single crystals of Fe₃GeTe₂ and (Ni_xFe_1-x)₃GeTe₂ (x = 0-1) were synthesized by chemical vapor transport and characterized using X-ray diffraction, Raman spectroscopy, and transmission electron microscopy. Angle-resolved polarized Raman spectroscopy resolved symmetry-dependent phonon modes and …