A5048135667- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Quasicrystal Structures and Properties
- Theoretical and Computational Physics
- Advanced Condensed Matter Physics
- Magnetic properties of thin films
- Crystallography and molecular interactions
- Machine Learning in Materials Science
- Physics of Superconductivity and Magnetism
- Luminescence and Fluorescent Materials
- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Quantum many-body systems
- Computational Drug Discovery Methods
- Synthesis and Properties of Aromatic Compounds
- Electrochemical Analysis and Applications
- Cellular Automata and Applications
- Supramolecular Self-Assembly in Materials
- Liquid Crystal Research Advancements
- Coronary Interventions and Diagnostics
- Algebraic structures and combinatorial models
- Force Microscopy Techniques and Applications
- Carbohydrate Chemistry and Synthesis
- Advanced Materials and Mechanics
- Magneto-Optical Properties and Applications
Columbia College - South Carolina
2025
University of Kentucky
2013-2024
Institute of Medical Sciences and Sum Hospital
2024
École Polytechnique Fédérale de Lausanne
2016-2023
Polish Academy of Sciences
2021-2023
Institute of Physics
2021-2023
United States Food and Drug Administration
2023
Dr. Hari Singh Gour University
2023
Indian Institute of Science Education and Research Thiruvananthapuram
2015-2020
Technical University of Munich
2016-2018
We have patterned novel Permalloy thin films with quasicrystalline Penrose $P2$ tilings and measured their dc magnetization ferromagnetic resonance absorption. Reproducible anomalies in the hysteretic, low-field data signal a series of abrupt transitions between ordered textures, culminating smooth evolution into saturated state. Micromagnetic simulations compare well to experimental hysteresis loops spectra indicate that systematic control magnetic reversal domain wall motion can be...
We report broadband spin-wave spectroscopy on kagome artificial spin ice (ASI) made of large arrays interconnected Ni$_{80}$Fe$_{20}$ nanobars. Spectra taken in saturated and disordered states exhibit a series resonances with characteristic magnetic field dependencies. Making use micromagnetic simulations, we identify that reflect the spin-solid-state monopole-antimonopole pairs Dirac strings. The latter allow for generation highly-charged vertices ASIs via microwave assisted switching. Our...
Materials design and discovery are often hampered by the slow pace materials human costs associated with Edisonian trial-and-error screening approaches. Recent advances in computational power, theoretical methods, data science techniques, however, being manifest a convergence of these tools to enable silico discovery. Here, we present development deployment analytic approaches for crystalline organic semiconductors. The OCELOT (Organic Crystals Electronic Light-Oriented Technologies)...
Accelerating the development of π-conjugated molecules for applications such as energy generation and storage, catalysis, sensing, pharmaceuticals, (semi)conducting technologies requires rapid accurate evaluation electronic, redox, or optical properties. While high-throughput computational screening has proven to be a tremendous aid in this regard, machine learning (ML) other data-driven methods can further enable orders magnitude reduction time while at same providing dramatic increases...
Organic semiconductors (OSCs) offer the capacity for distinctive and finely tuned electronic, optical, thermal, mechanical properties, making them of interest across a range energy generation storage, sensor, lighting, display, electronics applications. The pathway from molecular building block design to material, however, is complicated by complex synthesis– processing–structure–property–function relationships that are inherent OSCs. adoption artificial intelligence (AI) tools, including...
Abstract A simple procedure for the selective N-acylation of cytosine nucleosides has been developed by reacting appropriate nucleoside with acid anhydrides at room temperature employing N,N-dimethylformamide as solvent.
We have used scanning electron microscopy with polarization analysis and photoemission to image the two-dimensional magnetization of permalloy films patterned into Penrose P2 tilings (P2T). The interplay exchange interactions in asymmetrically coordinated vertices short-range dipole among connected film segments stabilize magnetically ordered, spatially distinct sublattices that coexist frustrated at room temperature. Numerical simulations include long-range between agree images as-grown P2T...
The static and dynamic magnetic responses of patterned ferromagnetic thin films are uniquely altered in the case aperiodic patterns that retain long-range order (e.g., quasicrystals). We have fabricated permalloy wire networks based on periodic square antidot lattices (ADLs) distorted according to an Fibonacci sequence applied two lattice translations, d1 = 1618 nm d2 1000 nm. segment thickness is fixed at t 25 nm, width W varies from 80 510 measured DC magnetization between room temperature...
Abstract Optoelectronic properties of anisotropic crystals vary with direction requiring that the orientation molecular organic semiconductor is controlled in optoelectronic device active layers to achieve optimal performance. Here, a generalizable strategy introduce periodic variations out‐of‐plane orientations 5,11‐bis(triisopropylsilylethynyl)anthradithiophene (TIPS ADT) presented. TIPS ADT crystallized from melt presence 16 wt.% polyethylene (PE) forms banded spherulites crystalline...
Organic mixed ionic–electronic conductors (OMIECs) have the potential to enable diverse new technologies, ranging from novel in situ biosensors flexible energy storage devices and neuromorphic computing platforms. However, their complex behavior functional films involving electrolyte-induced swelling, ion ingress, electrochemical doping inhibits rational material design. Of critical importance is an understanding of specific location ions volumetrically doped material, yet this information...
The D 3 TaLES database and data infrastructure aim to offer readily accessible uniform of varying types for redox-active organic molecules targeting non-aqueous redox flow batteries.
We report angular-dependent spin-wave spectroscopy on kagome artificial spin ice made of large arrays interconnected Ni80Fe20 nanobars. Spectra taken in saturated and disordered states exhibit a series resonances with characteristic in-plane angular dependencies. Micromagnetic simulations allow us to interpret two-step magnetization reversal the nanomagnets. The dynamic properties are consistent topological defects that provoked via magnetic field applied at specific angles. Simulations we...
Channels for high-speed propagation are interesting magnonic devices, where spin waves can be used as the information carriers. Unfortunately, exchange-dominated perpendicular standing suffer from low group velocities. This study uses a Y${}_{3}$Fe${}_{5}$O${}_{12}$/Ni${}_{81}$Fe${}_{19}$ bilayer in waveguide structure to enhance velocities of spin-wave modes. Other systems also explored optimize enhancement. work paves way high-performance directional couplers and multifrequency devices...
Abstract Quasicrystalline structures and aperiodic metamaterials find applications ranging from established consumer gadgets to potential high‐tech photonic components owing both complex arrangements of constituents exotic rotational symmetries. Magnonics is an evolving branch magnetism research where information transported via magnetization oscillations (magnons). Their control manipulation are so far best accomplished in periodic which exhibit properties artificially modulated on the...
ExpFlow, a software that allows the systematic encoding of laboratory workflows through graphical user interface, facilitates translation human-developed procedures to robotic experimentation.
Antidot lattices (ADLs) patterned into soft magnetic thin films exhibit rich ferromagnetic resonance (FMR) spectra corresponding to many different magnetization modes. One of the predicted modes is highly localized at edges antidots; this mode difficult detect experimentally. Here we present FMR data for a permalloy film square array antidots. Comparison these with micromagnetic simulations permits identification several edge Our also reveal effect antidot shape on dispersion.
We report angle-dependent spin-wave spectroscopy on aperiodic quasicrystalline magnetic lattices, i.e., Ammann, Penrose P2 and P3 lattices made of large arrays interconnected ${\mathrm{Ni}}_{80}\phantom{\rule{0.28em}{0ex}}{\mathrm{Fe}}_{20}$ nanobars. Spin-wave spectra obtained in the nearly saturated state contain distinct sets resonances with characteristic angular dependencies for applied in-plane fields. Micromagnetic simulations allow us to attribute detected mode profiles specific...
We have performed broadband (10 MHz–18 GHz) and narrowband (9.7 ferromagnetic resonance (FMR) measurements on permalloy thin films patterned with quasiperiodic Ammann tilings having eightfold rotational symmetry. observed highly reproducible mode structures in the low-frequency, hysteretic regime which domain walls unsaturated magnetization textures exist. A minimum of 10 robust modes were samples, compared to single uniform unpatterned films. The field dependence approximate symmetry FMR...
The crystallization of weakly fluorescent 4-amino-2,2′-bipyridine (<bold>AMBPY</bold>) in solution phase under ambient conditions afforded three conformational polymorphs possessing enhanced emission.
The rapid development and application of machine learning (ML) techniques in materials science have led to new tools for machine-enabled autonomous/high-throughput design discovery. Alongside, efforts extract data from traditional experiments the published literature with natural language processing (NLP) algorithms provide opportunities develop tremendous troves these silico discovery endeavors. While NLP is used all aspects society, its still very early stages. This perspective provides a...
We have performed broadband ferromagnetic resonance measurements on an artificial spin ice array using a microwave meanderline technique. In addition to uniform precessional mode, we observe additional mode that shows unusual, field-history dependent behavior.
Organic materials which can self-assemble into higher-order superstructures have extensive applications in artificial light-harvesting systems, solution-processable bulk-heterojunction solar cells, and photofunctional devices owing to their unique charge transport properties. In this report, we demonstrate a self-assembled nonsymmetric donor–acceptor triad (TAN) composed of triphenylamine (T), anthracene (A), naphthalimide (N) units, for achieving long-lived separation via aggregation....
The self-assembly of chiral organic chromophores is gaining huge significance due to the abundance supramolecular chirality found in natural systems. We report an interdigitated molecular assembly involving axially octabrominated perylenediimide (OBPDI) which transfers information achiral aromatic moieties. crystalline two-component assemblies OBPDI and electron-rich units were facilitated through π-hole⋅⋅⋅π donor-acceptor interactions, charge-transfer characteristics ground excited states...