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Gemini Near Infrared Spectrograph–Distant Quasar Survey: Augmented Spectroscopic Catalog and a Prescription for Correcting UV-based Quasar Redshifts (open access)

Gemini Near Infrared Spectrograph–Distant Quasar Survey: Augmented Spectroscopic Catalog and a Prescription for Correcting UV-based Quasar Redshifts

Article describes how quasars at z ≳ 1 most often have redshifts measured from rest-frame ultraviolet emission lines. One of the most common such lines, C ivλ1549, shows blueshifts up to ≈5000 km s−1 and in rare cases even higher. The authors present spectroscopic measurements for 260 sources at 1.55 ≲ z ≲ 3.50 having −28.0 ≲ Mi ≲ − 30.0 mag from the Gemini Near Infrared Spectrograph–Distant Quasar Survey (GNIRS-DQS) catalog, augmenting the previous iteration, which contained 226 of the 260 sources whose measurements are improved upon in this work.
Date: June 13, 2023
Creator: Matthews, Brandon M.; Dix, Cooper; Shemmer, Ohad; Brotherton, Michael S.; Myers, Adam D.; Andruchow, I. et al.
Object Type: Article
System: The UNT Digital Library
Gemini Near Infrared Spectrograph–Distant Quasar Survey: Prescriptions for Calibrating UV-based Estimates of Supermassive Black Hole Masses in High-redshift Quasars (open access)

Gemini Near Infrared Spectrograph–Distant Quasar Survey: Prescriptions for Calibrating UV-based Estimates of Supermassive Black Hole Masses in High-redshift Quasars

Article describes how the most reliable single-epoch supermassive black hole mass (MBH) estimates in quasars are obtained by using the velocity widths of low-ionization emission lines, typically the Hβλ4861 line. The authors find that utilizing both emission lines, where available, reduces the scatter of UV-based MBH estimates by ∼15% when compared to previous studies.
Date: June 13, 2023
Creator: Dix, Cooper; Matthews, Brandon; Shemmer, Ohad; Brotherton, Michael S.; Myers, Adam D.; Andruchow, I. et al.
Object Type: Article
System: The UNT Digital Library
Generation of over 1000 Diffraction Spots from 2D Graded Photonic Super-Crystals (open access)

Generation of over 1000 Diffraction Spots from 2D Graded Photonic Super-Crystals

Discusses a project in which researchers were able to generate over 1000 diffraction spots from a graded photonic super-crystal with a unit super-cell size of 12a × 12a where a is the lattice constant and hole radii are gradually changed in dual directions.
Date: April 10, 2020
Creator: Hassan, Safaa; Jiang, Yan; Alnasser, Khadijah; Hurley, Noah; Zhang, Hualiang; Philipose, Usha et al.
Object Type: Article
System: The UNT Digital Library
Growth of Highly-Ordered Metal Nanoparticle Arrays in the Dimpled Pores of an Anodic Aluminum Oxide Template (open access)

Growth of Highly-Ordered Metal Nanoparticle Arrays in the Dimpled Pores of an Anodic Aluminum Oxide Template

Article presents a reliable, scalable, and inexpensive technology for the fabrication of ordered arrays of metal nanoparticles with large areal coverage on various substrates. Using a simple model, the experimental results were interpreted and supported by numerical estimations.
Date: November 8, 2022
Creator: Farmer, Gavin; Abraham, James; Littler, Chris; Syllaios, A. J. & Philipose, Usha
Object Type: Article
System: The UNT Digital Library
High-Throughput Computational Search for Half-Metallic Oxides (open access)

High-Throughput Computational Search for Half-Metallic Oxides

The article describes a high-throughput computational search for half-metallic compounds. The analysis of calculated electronic properties of thousands of materials from the inorganic crystal structure database allowed the authors to identify potential half metals. They found over two-hundred strong half-metallic oxides; several of them have never been reported before.
Date: April 25, 2020
Creator: Liyanage, Laalitha S. I.; Slawińska, Jagoda; Gopal, Priya; Curtarolo, Stefano; Fornari, Marco & Buongiorno Nardelli, Marco
Object Type: Article
System: The UNT Digital Library
Holographic Fabrication of 3D Moiré Photonic Crystals Using Circularly Polarized Laser Beams and a Spatial Light Modulator (open access)

Holographic Fabrication of 3D Moiré Photonic Crystals Using Circularly Polarized Laser Beams and a Spatial Light Modulator

The authors of the article state that holographic fabrication of a 3D moiré photonic crystal is very difficult due to the coexistence of the bright and dark regions, where the exposure threshold is suitable for one region but not for the other. In this paper, the authors study the holographic fabrication of 3D moiré photonic crystals using an integrated system of a single reflective optical element (ROE) and a spatial light modulator (SLM) where nine beams (four inner beams + four outer beams + central beam) are overlapped.
Date: June 9, 2023
Creator: Hurley, Noah; Kamau, Steve; Cui, Jingbiao & Lin, Yuankun
Object Type: Article
System: The UNT Digital Library
Ice imaging in aircraft anti-icing fluid films using polarized light (open access)

Ice imaging in aircraft anti-icing fluid films using polarized light

Article presents how to enhance ice contrast in the visible spectrum by using ice birefringence and polarized light reflection. The method can be used for both visual inspection and automatic ice detection systems.
Date: December 13, 2021
Creator: Grishaev, Viktor G.; Usachev, Igor A.; Drachev, Vladimir P.; Gattarov, Ramil K.; Rudenko, Nadezhda I.; Amirfazli, Alidad et al.
Object Type: Article
System: The UNT Digital Library
Influence of Tools and Cutting Strategy on Milling Conditions and Quality of Horizontal Thin-Wall Structures of Titanium Alloy Ti6Al4V (open access)

Influence of Tools and Cutting Strategy on Milling Conditions and Quality of Horizontal Thin-Wall Structures of Titanium Alloy Ti6Al4V

Article describes how titanium and nickel alloys are used in the creation of components exposed to harsh and variable operating conditions. The authors state that a search is underway for cutting parameters that will minimize the vibration while meeting the quality requirements.
Date: December 18, 2023
Creator: Kurpiel, Szymon; Cudok, Bartosz; Zagórski, Krzysztof; Cieślik, Jacek; Skrzypkowski, Krzysztof & Brostow, Witold, 1934-
Object Type: Article
System: The UNT Digital Library
Laser Diffraction Zones and Spots from Three-Dimensional Graded Photonic Super-Crystals and Moiré Photonic Crystals (open access)

Laser Diffraction Zones and Spots from Three-Dimensional Graded Photonic Super-Crystals and Moiré Photonic Crystals

This article reports the holographic fabrication of three types of 3D graded photonic super-crystals (GPSCs) through nine beam interferences and their characteristic diffraction patterns.
Date: June 3, 2022
Creator: Hurley, Noah; Kamau, Steve; Alnasser, Khadijah; Philipose, Usha; Cui, Jingbiao & Lin, Yuankun
Object Type: Article
System: The UNT Digital Library
Long-range current-induced spin accumulation in chiral crystals (open access)

Long-range current-induced spin accumulation in chiral crystals

Article states that chiral materials, similarly to human hands, have distinguishable right-handed and left-handed enantiomers which may behave differently in response to external stimuli, so for the first time the authors use an approach based on the density functional theory (DFT)+PAOFLOW calculations to quantitatively estimate the so-called collinear Rashba–Edelstein effect (REE) that generates spin accumulation parallel to charge current and can manifest as chirality-dependent charge-to-spin conversion in chiral crystals. The authors reveal that the spin accumulation induced in the bulk by an electric current is intrinsically protected by the quasi-persistent spin helix arising from the crystal symmetries present in chiral systems with the Weyl spin–orbit coupling.
Date: November 18, 2022
Creator: Roy, Arunesh; Cerasoli, Frank T.; Jayaraj, Anooja; Tenzin, Karma; Buongiorno Nardelli, Marco & Sławińska, Jagoda
Object Type: Article
System: The UNT Digital Library
Long-range nonspreading propagation of sound beam through periodic layered structure (open access)

Long-range nonspreading propagation of sound beam through periodic layered structure

Article analyzing dispersion of sound in a solid-fluid layered structure and found a flex point on the isofrequency curve where D vanishes for given direction of propagation and frequency. Nonspreading propagation is experimentally observed in a water steel lattice of 75 periods (~1 meter long) and occurs in the regime of anomalous dispersion and strong acoustic anisotropy when the effective mass along periodicity is close to zero. Under these conditions the incoming beam experiences negative refraction of phase velocity leading to backward wave propagation. The observed effect is explained using a complete set of dynamical equations and our effective medium theory.
Date: September 2, 2020
Creator: Zubov, Yurii; Djafari-Rouhani, Bahram; Jin, Yuqi; Sofield, Mathew; Walker, Ezekiel; Neogi, Arup et al.
Object Type: Article
System: The UNT Digital Library
Longitudinal Monostatic Acoustic Effective Bulk Modulus and Effective Density Evaluation of Underground Soil Quality: A Numerical Approach (open access)

Longitudinal Monostatic Acoustic Effective Bulk Modulus and Effective Density Evaluation of Underground Soil Quality: A Numerical Approach

This article introduces a novel method using longitudinal sound to detect underground soil voids to inspect underwater bed property in terms of effective bulk modulus and effective density of the material properties.
Date: December 25, 2020
Creator: Jin, Yuqi; Choi, Tae-Youl & Neogi, Arup
Object Type: Article
System: The UNT Digital Library
Low-Energy Atomic Processes Including Ones Involving a Positron (open access)

Low-Energy Atomic Processes Including Ones Involving a Positron

Data management plan for the grant, "Low-Energy Atomic Processes Including Ones Involving a Positron." The proposed research in theoretical atomic physics involves few-body systems of charged particles, especially ones that involve the antiparticle of the electron, which is a positron. One of these systems is the positronium negative ion, which is comprised of two electrons and a positron. The exotic positronium atom is similar to the conventional hydrogen atom, but the positive charge in the atom is a positron rather than a proton. The proposed studies of these few-body charged systems will support international collaborations with scientists in the UK and Japan.
Date: 2022-09-01/2025-08-31
Creator: Quintanilla, Sandra J.
Object Type: Text
System: The UNT Digital Library
Magnetic confinement of effectively unmagnetized plasma particles (open access)

Magnetic confinement of effectively unmagnetized plasma particles

Article develops a planar model for an artificially structured boundary that may provide magnetic confinement of nonmagnetically trapped plasma particles.
Date: December 1, 2020
Creator: Ordonez, Carlos A.
Object Type: Article
System: The UNT Digital Library
Manufacturing and Characterization of Hybrid Bulk Voxelated Biomaterials Printed by Digital Anatomy 3D Printing (open access)

Manufacturing and Characterization of Hybrid Bulk Voxelated Biomaterials Printed by Digital Anatomy 3D Printing

This article proposes non-destructive ultrasound effective density and bulk modulus imaging to evaluate 3D voxelated materials printed by J750 Digital Anatomy 3D Printer of Stratasys. This method provides the design map of voxelated materials and substantially broadens the applications of 3D digital printing in the clinical research area.
Date: December 30, 2020
Creator: Heo, Hyeonu; Jin, Yuqi; Yang, David; Wier, Christopher; Minard, Aaron; Dahotre, Narendra B. et al.
Object Type: Article
System: The UNT Digital Library
A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium (open access)

A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium

Article using simulations and experimental measurements to design, build, and test a compact and uniform magnetic field source and then apply it to the optical pumping of atomic helium.
Date: September 24, 2021
Creator: Cameron, Garnet; Cuevas, Jonathan; Pound, Jeffrey Jr. & Shiner, David
Object Type: Article
System: The UNT Digital Library
Momentum-Space Spin Antivortex and Spin Transport in Monolayer Pb (open access)

Momentum-Space Spin Antivortex and Spin Transport in Monolayer Pb

This article finds a nontrivial spin texture, spin antivortex, can appear at certain momenta on the Γ− K line in a 2D monolayer Pb on top of SiC.
Date: April 21, 2022
Creator: Yang, Kaijie; Wang, Yuanxi & Liu, Chao-Xing
Object Type: Article
System: The UNT Digital Library
Multitask deep-learning-based design of chiral plasmonic metamaterials (open access)

Multitask deep-learning-based design of chiral plasmonic metamaterials

This article presents an end-to-end functional bidirectional deep-learning (DL) model for three-dimensional chiral metamaterial design and optimization. This ML model utilizes multitask joint learning features to recognize, generalize, and explore in detail the nontrivial relationship between the metamaterials’ geometry and their chiroptical response, eliminating the need for auxiliary networks or equivalent approaches to stabilize the physically relevant output. This model efficiently realizes both forward and inverse retrieval tasks with great precision, offering a promising tool for iterative computational design tasks in complex physical systems. Other potential applications include photodetectors, polarization-resolved imaging, and circular dichroism (CD) spectroscopy.
Date: July 1, 2020
Creator: Ashalley, Eric; Acheampong, Kingsley; Besteiro, Lucas V.; Yu, Peng; Neogi, Arup; Govorov, Alexander O. et al.
Object Type: Article
System: The UNT Digital Library
Novel 2D Dynamic Elasticity Maps for Inspection of Anisotropic Properties in Fused Deposition Modeling Objects (open access)

Novel 2D Dynamic Elasticity Maps for Inspection of Anisotropic Properties in Fused Deposition Modeling Objects

Article introducing a novel ultrasonic non-destructive and non-invasive elastography method demonstrated to evaluate the mechanical properties of fused deposition modeling 3D printed objects using two-dimensional dynamical elasticity mapping. Based on the recently investigated dynamic bulk modulus and effective density imaging technique, an angle-dependent dynamic shear modulus measurement was performed to extract the dynamic Young’s modulus distribution of the FDM structures. The elastographic image analysis demonstrated the presence of anisotropic dynamic shear modulus and dynamic Young’s modulus existing in the fused deposition modeling 3D printed objects. The non-destructive method also differentiated samples with high contrast property zones from that of low contrast property regions. The angle-dependent elasticity contrast behavior from the ultrasonic method was compared with conventional and static tensile tests characterization. A good correlation between the nondestructive technique and the tensile test measurements was observed.
Date: August 30, 2020
Creator: Jin, Yuqi; Yang, Teng; Heo, Hyeonu; Krokhin, Arkadii A.; Shi, Sheldon; Dahotre, Narendra B. et al.
Object Type: Article
System: The UNT Digital Library
Numerical Investigation of Dynamical and Morphological Trends in Relativistic Jets (open access)

Numerical Investigation of Dynamical and Morphological Trends in Relativistic Jets

Article investigates the connection of kiloparsec scale AGN jet properties to their intrinsic parameters and surroundings. This is the accepted manuscript version of the article.
Date: August 2022
Creator: Mandal, Soham; Duffell, Paul C. & Li, Yuan
Object Type: Article
System: The UNT Digital Library
Optical Pump Terahertz Probe (OPTP) and Time Resolved Terahertz Spectroscopy (TRTS) of emerging solar materials Editor’s Pick (open access)

Optical Pump Terahertz Probe (OPTP) and Time Resolved Terahertz Spectroscopy (TRTS) of emerging solar materials Editor’s Pick

Article describes how photoconductivity is the crucial benchmark to assess the potential of any emerging material for future solar applications. This tutorial aims to familiarize the reader with the main THz techniques used to explore emerging materials.
Date: July 19, 2023
Creator: Neu, Jens
Object Type: Article
System: The UNT Digital Library
Optimization of the Observing Cadence for the Rubin Observatory Legacy Survey of Space and Time: A Pioneering Process of Community-focused Experimental Design (open access)

Optimization of the Observing Cadence for the Rubin Observatory Legacy Survey of Space and Time: A Pioneering Process of Community-focused Experimental Design

This article is part of a Focus Issue on the topic of Rubin LSST Survey Strategy Optimization. The motivation, history, and decision-making process of the observing strategy optimization are detailed, giving context to the science-driven proposals and recommendations for the survey strategy included in this Focus Issue.
Date: December 22, 2021
Creator: Bianco, Federica B.; Ivezić, Željko; Jones, R. Lynne; Graham, Melissa L.; Marshall, Phil; Saha, Abhijit et al.
Object Type: Article
System: The UNT Digital Library
Phononic crystal as a homogeneous viscous metamaterial (open access)

Phononic crystal as a homogeneous viscous metamaterial

Article develops a homogenization theory, representing the low-frequency limit for a phononic crystal of cylinders embedded in a viscous fluid.
Date: June 8, 2020
Creator: Krokhin, Arkadii A.; Zubov, Yu.; Ibarias, M. & Arriaga, J.
Object Type: Article
System: The UNT Digital Library
Photonic Band Gaps and Resonance Modes in 2D Twisted Moiré Photonic Crystal (open access)

Photonic Band Gaps and Resonance Modes in 2D Twisted Moiré Photonic Crystal

Article studying 2D twisted moiré photonic crystals without physical rotation and simulating their photonic band gaps in photonic crystals formed at different twisted angles, different gradient levels, and different dielectric filling factors.
Date: September 23, 2021
Creator: Alnasser, Khadijah; Kamau, Steve; Hurley, Noah; Cui, Jingbiao & Lin, Yuankun
Object Type: Article
System: The UNT Digital Library