Naturally Layered Aurivillius Phases: Flexible Scaffolds for the Design of Multiferroic Materials

The Aurivillius layer-structures, described by the general formula Bi2O2(Am-1BmO3m+1), are naturally 2-dimensionally nanostructured. They are very flexible frameworks for a wide variety of applications, given that different types of cations can beaccommodated both at the A- and B-sites. In this review article, we describe how the Aurivillius phases are a particularly attractive class of oxides for the design of prospective single phase multiferroic systems for multi-state data storage applications, as they offer the potential to include substantial amounts of magnetic cations within a strongly ferroelectric system. The ability to vary m yields differing numbers of symmetrically distinct B-site locations over which the magnetic cations can be distributed and generates driving forces for cation partitioning and magnetic ordering. We discuss how out-of-phase boundary and stacking fault defects can further influence local stoichiometry and the extent of cation partitioning in these intriguing material systems.

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Combining Magnetism and Ferroelectricity towards Multiferroicity

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.189.15 ◽

2012 ◽

Vol 189 ◽

pp. 15-40

Author(s):

Dinesh Shukla ◽

Nhalil E. Rajeevan ◽

Ravi Kumar

Keyword(s):

Long Range ◽

Recent Progress ◽

Single Phase ◽

Magnetoelectric Effect ◽

Condensed Matter ◽

Ferroelectric Properties ◽

Magnetic Ordering ◽

Electric Polarization ◽

Multiferroic Materials ◽

The Past

The attempts to combine both the magnetic and ferroelectric properties in one material started in 1960s predominantly by the group of Smolenskii and Schmid [1. Dzyaloshinskii first presented the theory for multiferroicity in Cr2O3, which was soon experimentally confirmed by Astrov [5,. Further work on multiferroics was done by the group of Smolenskii in St. Petersburg (then Leningrad) [7, but the term multiferroic was first used by H. Schmid in 1994 [. These efforts have resulted in many fundamental observations and opened up an entirely new field of study. Schmid [ defined the multiferroics as single phase materials which simultaneously possess two or more primary ferroic properties. The term multiferroic has been expanded to include materials which exhibit any type of long range magnetic ordering, spontaneous electric polarization, and/or ferroelasticity. In the past decade, several hundreds of papers related to multiferroic materials and magnetoelectric effect have been published every year, making this topic one of the hottest areas in condensed matter physics from fundamental science as well as applications viewpoints. This article sheds light on recent progress about the developments of new multiferroics by combining unconventional magnetism and ferroelectricity with an emphasis on Bi based multiferroic materials. Specifically results of Ti doped BiMn2O5and Bi doped Co2MnO4multiferroics are discussed.

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Linear phase encoding for holographic data storage with a single phase-only spatial light modulator

Applied Optics ◽

10.1364/ao.55.002565 ◽

2016 ◽

Vol 55 (10) ◽

pp. 2565 ◽

Cited By ~ 10

Author(s):

Teruyoshi Nobukawa ◽

Takanori Nomura

Keyword(s):

Data Storage ◽

Spatial Light Modulator ◽

Single Phase ◽

Holographic Data Storage ◽

Linear Phase ◽

Light Modulator ◽

Phase Encoding

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Comparative investigations on different types of inductors in single-phase inverter

Journal of Physics Conference Series ◽

10.1088/1742-6596/2107/1/012051 ◽

2021 ◽

Vol 2107 (1) ◽

pp. 012051

Author(s):

M. Z. Aihsan ◽

A. M. Yusof ◽

Hasliza A Rahim ◽

B. Ismail ◽

W. A. Mustafa ◽

...

Keyword(s):

Pulse Width ◽

Single Unit ◽

Single Phase ◽

Pulse Width Modulation ◽

Bridge Circuit ◽

Experimental Assessment ◽

Phase Inverter ◽

Different Types ◽

Single Phase Inverter ◽

Validation Of Results

Abstract This article organized in two sections where it compares the performance of single-phase inverters using various types of inductors with differences modulation technique of pulse width modulation (PWM). Not all inductors perform the same function, even the inductance value is the same. The study will investigate the capability of each inductor on its performance to convert the unfiltered AC voltage into filtered sinusoidal AC voltage. The drum core and toroidal core inductors were used in this investigation. For both inductors, the performance will be analyzed based on Bipolar and Unipolar switching schemes in a single unit H-bridge circuit. The validation of results are through experimental assessment only and it will be evaluating the shape of sinusoidal AC voltage and the content of total harmonics distortion in the AC voltage for both inductors.

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Magnetoelectricity in multiferroics: a theoretical perspective

National Science Review ◽

10.1093/nsr/nwz023 ◽

2019 ◽

Vol 6 (4) ◽

pp. 629-641 ◽

Cited By ~ 27

Author(s):

Shuai Dong ◽

Hongjun Xiang ◽

Elbio Dagotto

Keyword(s):

Single Phase ◽

Theoretical Perspective ◽

Physical Property ◽

Present Review ◽

Multiferroic Materials ◽

Fundamental Physics ◽

Physical Mechanisms

ABSTRACT The key physical property of multiferroic materials is the existence of coupling between magnetism and polarization, i.e. magnetoelectricity. The origin and manifestations of magnetoelectricity can be very different in the available plethora of multiferroic systems, with multiple possible mechanisms hidden behind the phenomena. In this review, we describe the fundamental physics that causes magnetoelectricity from a theoretical viewpoint. The present review will focus on mainstream physical mechanisms in both single-phase multiferroics and magnetoelectric heterostructures. The most recent tendencies addressing possible new magnetoelectric mechanisms will also be briefly outlined.

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Plasma-Assisted Chemical Vapor Deposition of F-Doped MnO2 Nanostructures on Single Crystal Substrates

Nanomaterials ◽

10.3390/nano10071335 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1335

Author(s):

Lorenzo Bigiani ◽

Chiara Maccato ◽

Alberto Gasparotto ◽

Cinzia Sada ◽

Elza Bontempi ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

Data Storage ◽

Vapor Deposition ◽

Oxygen Deficiency ◽

Chemical Vapor ◽

Magnetic Ordering ◽

Analytical Techniques ◽

Structural Features ◽

Optical Absorption Spectroscopy ◽

Magnetic Characteristics

MnO2 nanostructures were fabricated by plasma assisted-chemical vapor deposition (PA-CVD) using a fluorinated diketonate diamine manganese complex, acting as single-source precursor for both Mn and F. The syntheses were performed from Ar/O2 plasmas on MgAl2O4(100), YAlO3(010), and Y3Al5O12(100) single crystals at a growth temperature of 300 °C, in order to investigate the substrate influence on material chemico-physical properties. A detailed characterization through complementary analytical techniques highlighted the formation of highly pure and oriented F-doped systems, comprising the sole β-MnO2 polymorph and exhibiting an inherent oxygen deficiency. Optical absorption spectroscopy revealed the presence of an appreciable Vis-light harvesting, of interest in view of possible photocatalytic applications in pollutant degradation and hydrogen production. The used substrates directly affected the system structural features, as well as the resulting magnetic characteristics. In particular, magnetic force microscopy (MFM) measurements, sensitive to the out-of-plane magnetization component, highlighted the formation of spin domains and long-range magnetic ordering in the developed materials, with features dependent on the system morphology. These results open the door to future engineering of the present nanostructures as possible magnetic media for integration in data storage devices.

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Physical Principles Underlying the Complex Biology of Intracellular Phase Transitions

Annual Review of Biophysics ◽

10.1146/annurev-biophys-121219-081629 ◽

2020 ◽

Vol 49 (1) ◽

pp. 107-133 ◽

Cited By ~ 74

Author(s):

Jeong-Mo Choi ◽

Alex S. Holehouse ◽

Rohit V. Pappu

Keyword(s):

Phase Transitions ◽

Rheological Properties ◽

Recent Work ◽

Driving Forces ◽

Rna Molecules ◽

Associative Polymers ◽

Different Types ◽

Condensate Formation ◽

The Impact ◽

Physical Principles

Many biomolecular condensates appear to form via spontaneous or driven processes that have the hallmarks of intracellular phase transitions. This suggests that a common underlying physical framework might govern the formation of functionally and compositionally unrelated biomolecular condensates. In this review, we summarize recent work that leverages a stickers-and-spacers framework adapted from the field of associative polymers for understanding how multivalent protein and RNA molecules drive phase transitions that give rise to biomolecular condensates. We discuss how the valence of stickers impacts the driving forces for condensate formation and elaborate on how stickers can be distinguished from spacers in different contexts. We touch on the impact of sticker- and spacer-mediated interactions on the rheological properties of condensates and show how the model can be mapped to known drivers of different types of biomolecular condensates.

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Ternary Stannides RE3Ru4Sn13 (RE = La, Ce, Pr, Nd) – Structure, Magnetic Properties, and 119Sn Mössbauer Spectroscopy

Zeitschrift für Naturforschung B ◽

10.1515/znb-2011-0702 ◽

2011 ◽

Vol 66 (7) ◽

pp. 664-670

Author(s):

◽

Christian Schwickert ◽

Thorsten Langer ◽

Rainer Pöttgen

Keyword(s):

Mössbauer Spectroscopy ◽

Mossbauer Spectroscopy ◽

Three Dimensional ◽

Magnetic Ordering ◽

119Sn Mössbauer Spectroscopy ◽

X Ray Diffraction ◽

Temperature Dependent ◽

Mößbauer Spectroscopy ◽

Arc Melting ◽

Different Types

The ternary stannides RE3Ru4Sn13 (RE = La, Ce, Pr, Nd) were obtained by arc-melting of the elements. The polycrystalline samples were characterized by powder X-ray diffraction. The structures of three compounds were refined from single-crystal diffractometer data: Yb3Rh4Sn13 type, Pm3̄n, a = 977.74(3) pm, wR2 = 0.0379, 280 F2 values for La3Ru4Sn13, a = 971.34(9) pm, wR2 = 0.0333, 274 F2 values for Ce3Ru4Sn13, a = 970.68(8) pm, wR2 = 0.0262, 272 F2 values for Nd3Ru4Sn13 with 13 variables per refinement. The structures consist of three-dimensional networks of condensed RuSn6/2 trigonal prisms with the RE (CN 16) and Sn2 (CN 12) atoms in two different types of cavities of the networks. The two crystallographically independent tin sites have been resolved by 119Sn Mössbauer spectroscopy. Temperature-dependent magnetic susceptibility measurements of Ce3Ru4Sn13 gave a reduced magnetic moment of 2.32 μB per Ce atom, indicating intermediate cerium valence. No magnetic ordering was evident down to 3 K.

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Amino Acids and Peptides as Versatile Ligands in the Synthesis of Antiproliferative Gold Complexes

Chemistry ◽

10.3390/chemistry2020013 ◽

2020 ◽

Vol 2 (2) ◽

pp. 203-218 ◽

Cited By ~ 2

Author(s):

Tina P. Andrejević ◽

Biljana Đ. Glišić ◽

Miloš I. Djuran

Keyword(s):

Rheumatoid Arthritis ◽

Amino Acids ◽

Future Development ◽

Antitumor Agents ◽

Review Article ◽

Gold Complexes ◽

Different Types ◽

Potential Antitumor

Gold complexes have been traditionally employed in medicine, and currently, some gold(I) complexes, such as auranofin, are clinically used in the treatment of rheumatoid arthritis. In the last decades, both gold(I) and gold(III) complexes with different types of ligands have gained considerable attention as potential antitumor agents, showing superior activity both in vitro and in vivo to some of the clinically used agents. The present review article summarizes the results achieved in the field of synthesis and evaluation of gold complexes with amino acids and peptides moieties for their cytotoxicity. The first section provides an overview of the gold(I) complexes with amino acids and peptides, which have shown antiproliferative activity, while the second part is focused on the activity of gold(III) complexes with these ligands. A systematic summary of the results achieved in the field of gold(I/III) complexes with amino acids and peptides could contribute to the future development of metal complexes with these biocompatible ligands as promising antitumor agents.

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Problems In Realistic Modelling Of Interfacial Reactions

MRS Proceedings ◽

10.1557/proc-54-97 ◽

1985 ◽

Vol 54 ◽

Cited By ~ 4

Author(s):

Charles W. Allen ◽

Gordon A Sargent

Keyword(s):

Single Phase ◽

Driving Forces ◽

Thermodynamic Description ◽

Nucleation Theory ◽

Initial Reaction ◽

Thermodynamic Prediction ◽

Multiple Product ◽

Solid Liquid ◽

Reaction Processes ◽

Reaction Problem

ABSTRACTFor modelling the reaction of chemically distinct materials in which intermediate alloy phases are formed a simple thermodynamic description is not adequate. Despite thermodynamic prediction of multiple product phases, a single phase generally forms first which is not necessarily that of greatest thermodynamic stability or of simplest structure. Such initial reaction processes may be modelled as metastable perltectoid (solid-solid) or perltectlc (solid-liquid) reactions, characterized by large thermodynamic driving forces with superimposed kinetic and morphological constraints. The interfacial reaction problem is reviewed in light of heterogeneous nucleation theory with emphasis on non-classical aspects.

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