55 research outputs found
Complexation of 1,3-dihetaryl-5-phenyl-2-pyrazoline Derivatives with Polyvalent Metal Ions: Quantum Chemical Modeling and Experimental Investigation
1,3,5-Triaryl-2-pyrazoline derivatives with a pyridine ring in position 1 and 2-benzimidazolyl or 2-benzothiazolyl bicycles in position 3 were synthesized. Spectral properties in solvents of similar polarity, i.e. aprotic acetonitrile and in protic methanol, were studied, complexation with cadmium and mercury ions in acetonitrile was elucidated as well. Quantum-chemical modeling with application of the elements of Bader's atoms-in-molecules (AIM) theory of the title molecules conformational structure and 1:1 stoichiometry complexes formed with polyvalent metals of various nature (Mg, Zn, Cd, Pb, Hg, Ba) was conducted. The principal possibility of “nitrogen-sulfur” switching of the metal ions binding sites for the benzothiazole derivative was revealed, and makes possible to classify this compound as “smart ligand”
Adiabatic Control of Spin-Wave Propagation using Magnetisation Gradients
Spin waves are of large interest as data carriers for future logic devices.
However, due to the strong anisotropic dispersion relation of dipolar
spin-waves in in-plane magnetised films the realisation of two-dimensional
information transport remains a challenge. Bending of the energy flow is
prohibited since energy and momentum of spin waves cannot be conserved while
changing the direction of wave propagation. Thus, non-linear or non-stationary
mechanisms are usually employed. Here, we propose to use reconfigurable
laser-induced magnetisation gradients to break the system's translational
symmetry. The resulting changes in the magnetisation shift the dispersion
relations locally and allow for operating with different spin-wave modes at the
same frequency. Spin-wave momentum is first transformed via refraction at the
edge of the magnetisation gradient region and then adiabatically modified
inside it. Along these lines the spin-wave propagation direction can be
controlled in a broad frequency range with high efficiency
Perspective on Nanoscaled Magnonic Networks
With the rapid development of artificial intelligence in recent years,
mankind is facing an unprecedented demand for data processing. Today, almost
all data processing is performed using electrons in conventional complementary
metal-oxide-semiconductor (CMOS) circuits. Over the past few decades,
scientists have been searching for faster and more efficient ways to process
data. Now, magnons, the quanta of spin waves, show the potential for higher
efficiency and lower energy consumption in solving some specific problems.
While magnonics remains predominantly in the realm of academia, significant
efforts are being made to explore the scientific and technological challenges
of the field. Numerous proof-of-concept prototypes have already been
successfully developed and tested in laboratories. In this article, we review
the developed magnonic devices and discuss the current challenges in realizing
magnonic circuits based on these building blocks. We look at the application of
spin waves in neuromorphic networks, stochastic and reservoir computing and
discuss the advantages over conventional electronics in these areas. We then
introduce a new powerful tool, inverse design magnonics, which has the
potential to revolutionize the field by enabling the precise design and
optimization of magnonic devices in a short time. Finally, we provide a
theoretical prediction of energy consumption and propose benchmarks for
universal magnonic circuits.Comment: 9 pages, 1 figur
Nanoscaled magnon transistor based on stimulated three-magnon splitting
Magnonics is a rapidly growing field, attracting much attention for its
potential applications in data transport and processing. Many individual
magnonic devices have been proposed and realized in laboratories. However, an
integrated magnonic circuit with several separate magnonic elements has yet not
been reported due to the lack of a magnonic amplifier to compensate for
transport and processing losses. The magnon transistor reported in [Nat.
Commun. 5, 4700, (2014)] could only achieve a gain of 1.8, which is
insufficient in many practical cases. Here, we use the stimulated three-magnon
splitting phenomenon to numerically propose a concept of magnon transistor in
which the energy of the gate magnons at 14.6 GHz is directly pumped into the
energy of the source magnons at 4.2 GHz, thus achieving the gain of 9. The
structure is based on the 100 nm wide YIG nano-waveguides, a directional
coupler is used to mix the source and gate magnons, and a dual-band magnonic
crystal is used to filter out the gate and idler magnons at 10.4 GHz frequency.
The magnon transistor preserves the phase of the signal and the design allows
integration into a magnon circuit.Comment: 8 pages, 3 figure
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