Bryan C. Chakoumakos
YOU?
Author Swipe
View article: Fingerprinting the Water and Vacancy Sites in Superhydrous Hematite: Neutron Scattering and First Principles Studies
Fingerprinting the Water and Vacancy Sites in Superhydrous Hematite: Neutron Scattering and First Principles Studies Open
Hematite (α-Fe2O3) is a low-cost, naturally abundant, and stable iron oxide with promising applications in energy applications such as photoelectrochemical water splitting, piezocatalysis, and microbial fuel cells. A superhydrous form, hyd…
View article: Spin-lattice entanglement in $\mathbf{CoPS}_3$
Spin-lattice entanglement in $\mathbf{CoPS}_3$ Open
Complex chalcogenides in the $M$PS$_3$ family of materials ($M$ = Mn, Fe, Co, and Ni) display remarkably different phase progressions depending upon the metal center orbital filling, character of the P-P linkage, and size of the van der Wa…
View article: Integrated AI/ML and HPC Framework for Multidimensional Neutron Crystallography
Integrated AI/ML and HPC Framework for Multidimensional Neutron Crystallography Open
Neutron time-of-flight (TOF) event data at the Spallation Neutron Source (SNS) provides a wealth of temporal information in multidimensional diffraction and parameter spaces. However, current analysis methods rely on sequential steps that …
View article: Integrated edge-to-exascale workflow for real-time steering in neutron scattering experiments
Integrated edge-to-exascale workflow for real-time steering in neutron scattering experiments Open
We introduce a computational framework that integrates artificial intelligence (AI), machine learning, and high-performance computing to enable real-time steering of neutron scattering experiments using an edge-to-exascale workflow. Focusi…
View article: Real-Time Atomic-Scale Structural Analysis Resolves the Amorphous to Crystalline CaCO<sub>3</sub> Mechanism Controversy
Real-Time Atomic-Scale Structural Analysis Resolves the Amorphous to Crystalline CaCO<sub>3</sub> Mechanism Controversy Open
Amorphous calcium carbonate (ACC) occurs as a precursor to geological and biogenic calcium carbonate (CaCO3), yet its transformation pathways and reaction mechanisms remain inconsistent and controversial. In this study, we inves…
View article: Giant Modulation of Refractive Index from Picoscale Atomic Displacements
Giant Modulation of Refractive Index from Picoscale Atomic Displacements Open
It is shown that structural disorder—in the form of anisotropic, picoscale atomic displacements—modulates the refractive index tensor and results in the giant optical anisotropy observed in BaTiS 3 , a quasi‐1D hexagonal chalcogenide. Sing…
View article: Giant Modulation of Refractive Index from Picoscale Atomic Displacements
Giant Modulation of Refractive Index from Picoscale Atomic Displacements Open
Structural disorder has been shown to enhance and modulate magnetic, electrical, dipolar, electrochemical, and mechanical properties of materials. However, the possibility of obtaining novel optical and optoelectronic properties from struc…
View article: Charge Density Wave Order and Electronic Phase Transitions in a Dilute <i>d</i>‐Band Semiconductor
Charge Density Wave Order and Electronic Phase Transitions in a Dilute <i>d</i>‐Band Semiconductor Open
As one of the most fundamental physical phenomena, charge density wave (CDW) order predominantly occurs in metallic systems such as quasi‐1D metals, doped cuprates, and transition metal dichalcogenides, where it is well understood in terms…
View article: Colossal Optical Anisotropy from Atomic‐Scale Modulations
Colossal Optical Anisotropy from Atomic‐Scale Modulations Open
Materials with large birefringence (Δ n , where n is the refractive index) are sought after for polarization control (e.g., in wave plates, polarizing beam splitters, etc.), nonlinear optics, micromanipulation, and as a platform for unconv…
View article: Anisotropic magnetism of the Shastry-Sutherland lattice material <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Ba</mml:mi><mml:msub><mml:mi>Nd</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:mi>Pt</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>5</mml:mn></mml:msub></mml:mrow></mml:math>
Anisotropic magnetism of the Shastry-Sutherland lattice material Open
For this work, single crystals were grown and characterized to investigate the physical properties and magnetic ground state of BaNd2PtO5, a candidate to host physics of the Shastry-Sutherland model. Analysis of singl…
View article: Vaterite Optical Petrography in Lake Sturgeon Otoliths
Vaterite Optical Petrography in Lake Sturgeon Otoliths Open
Vaterite occurring in fish otoliths exhibits plumose and spherulitic habits, the latter being like those grown from aqueous solutions. Vaterite spherulites are known to have sheaf-like texture and can be up to 100 μm in size. In thin secti…
View article: Machine-learning-assisted automation of single-crystal neutron diffraction
Machine-learning-assisted automation of single-crystal neutron diffraction Open
Neutron scattering is a powerful but expensive technique to study materials and discover new matter. Advanced detector technology has significantly improved the efficiency of neutron experiments, increasing the complexity of neutron data r…
View article: Colossal optical anisotropy from atomic-scale modulations: manuscript data
Colossal optical anisotropy from atomic-scale modulations: manuscript data Open
Relevant data files for Main Text figures of "Colossal optical anisotropy from atomic-scale modulations" Relevant data files for Supplementary Information figures of "Colossal optical anisotropy from atomic-scale modulations"
View article: Colossal optical anisotropy from atomic-scale modulations
Colossal optical anisotropy from atomic-scale modulations Open
In modern optics, materials with large birefringence (Δn, where n is the refractive index) are sought after for polarization control (e.g. in wave plates, polarizing beam splitters, etc.), nonlinear optics and quantum optics (e.g. for phas…
View article: Colossal optical anisotropy from atomic-scale modulations: manuscript data
Colossal optical anisotropy from atomic-scale modulations: manuscript data Open
Relevant data files for Main Text figures of "Colossal optical anisotropy from atomic-scale modulations" Relevant data files for Supplementary Information figures of "Colossal optical anisotropy from atomic-scale modulations"
View article: CSD 2215916: Experimental Crystal Structure Determination
CSD 2215916: Experimental Crystal Structure Determination Open
An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely availabl…
View article: CSD 2215917: Experimental Crystal Structure Determination
CSD 2215917: Experimental Crystal Structure Determination Open
An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely availabl…
View article: Crystal Growth and Phase Formation of High-Entropy Rare-Earth Aluminum Perovskites
Crystal Growth and Phase Formation of High-Entropy Rare-Earth Aluminum Perovskites Open
In this work, we demonstrate for the first time the crystal growth of high-entropy rare-earth (RE) aluminum perovskites (REAlO3) using the micro-pulling-down method to inform future exploration of functional crystals. To determi…
View article: Direct Visualization of Magnetic Correlations in Frustrated Spinel ZnFe<sub>2</sub>O<sub>4</sub>
Direct Visualization of Magnetic Correlations in Frustrated Spinel ZnFe<sub>2</sub>O<sub>4</sub> Open
Magnetic materials with the spinel structure (A 2+ B 3+ 2 O 4 ) form the core of numerous magnetic devices, and ZnFe 2 O 4 constitutes a peculiar example where the nature of the magnetism is still unresolved. Susceptibility measurements re…
View article: Tuning the melting point and phase stability of rare-earth oxides to facilitate their crystal growth from the melt
Tuning the melting point and phase stability of rare-earth oxides to facilitate their crystal growth from the melt Open
The challenge of growing rare-earth (RE) sesquioxide crystals can be overcome by tailoring their structural stability and melting point via composition engineering. This work contributes to the advancement of the field of crystal growth of…
View article: Direct visualization of magnetic correlations in frustrated spinel ZnFe$_2$O$_4$
Direct visualization of magnetic correlations in frustrated spinel ZnFe$_2$O$_4$ Open
Magnetic materials with the spinel structure (A$^{2+}$B$^{3+}_2$O$^4$) form the core of numerous magnetic devices, but ZnFe$_2$O$_4$ constitutes a peculiar example where the nature of the magnetism is still unresolved. Susceptibility measu…
View article: Unconventional Charge-density-wave Order in a Dilute d-band Semiconductor
Unconventional Charge-density-wave Order in a Dilute d-band Semiconductor Open
Electron-lattice coupling effects in low dimensional materials give rise to charge density wave (CDW) order and phase transitions. These phenomena are critical ingredients for superconductivity and predominantly occur in metallic model sys…
View article: PIONEER, a high-resolution single-crystal polarized neutron diffractometer
PIONEER, a high-resolution single-crystal polarized neutron diffractometer Open
PIONEER is a high Q-resolution, single-crystal, polarized neutron diffractometer at the Second Target Station (STS), Oak Ridge National Laboratory. It will provide the unprecedented capability of measuring tiny crystals (0.001 mm3, i.e., x…
View article: CSD 2170235: Experimental Crystal Structure Determination
CSD 2170235: Experimental Crystal Structure Determination Open
An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely availabl…
View article: CSD 2170234: Experimental Crystal Structure Determination
CSD 2170234: Experimental Crystal Structure Determination Open
An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely availabl…
View article: CSD 2170236: Experimental Crystal Structure Determination
CSD 2170236: Experimental Crystal Structure Determination Open
An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely availabl…
View article: Effects of composition and growth parameters on phase formation in multicomponent aluminum garnet crystals
Effects of composition and growth parameters on phase formation in multicomponent aluminum garnet crystals Open
The effects of composition on the phase formation of multicomponent garnet crystals grown via directional solidification by the micro-pulling-down method are studied. A relatively wide range of rare-earth (RE) average ionic radii (AIR) is …
View article: The effects of oxygen and strontium vacancies on the superconductivity of single crystals of Bi sub 2 Sr sub 2-x CuO sub 6-y
The effects of oxygen and strontium vacancies on the superconductivity of single crystals of Bi sub 2 Sr sub 2-x CuO sub 6-y Open
Single crystals of Bi{sub 2}Sr{sub 2-x}CuO{sub 6-y} were grown from CuO-rich melts. The Sr content in the crystals was varied from x=0.1 to x=0.5 by varying the starting composition of the melt and the oxygen content was adjusted using an …
View article: Quantifying fish otolith mineralogy for trace-element chemistry studies
Quantifying fish otolith mineralogy for trace-element chemistry studies Open
View article: Toward an Autonomous Workflow for Single Crystal Neutron Diffraction
Toward an Autonomous Workflow for Single Crystal Neutron Diffraction Open