Rashid Giyasovich Nazmitdinov

We report a facile and environmentally benign strategy to produce highly stable aqueous colloids of the CsPbBr3@CsPb2Br5 core−shell nanocomposites via water-driven in situ reconstruction. A combination of X-ray diffraction, energy-dispersive X-ray spectroscopy, and real-time conductometry confirms the water-induced phase transformation. This reconstruction process involves the selective leaching of Cs+ and Br− ions during brief ultrasonication in water from the multiphase CsPbBr3/Cs4PbBr6 precursor, synthesized via a facile, low-toxicity ligand-assisted reprecipitation method. Transmission electron microscopy establishes the matrix-inclusion nanocomposite geometry, confirming that monodisperse orthorhombic CsPbBr3 cores with a mean diameter of (3.58 ± 0.57) nm are embedded within the tetragonal CsPb2Br5 matrix. Time-resolved photoluminescence spectroscopy proves effective surface defect passivation, exhibiting an extension of the average carrier lifetime from 4.43 ns to 5.30 ns upon shell crystallization. Driven by this defect passivation, photoluminescence spectroscopy confirms a maximum photoluminescence quantum yield of 48.6% after 72 h of storage. Laser Doppler microelectrophoresis determines a high positive surface potential of (74.5 ± 13.7) mV ensuring long-term colloidal stability exceeding >1000 h without sedimentation. Time-dependent fluorescence spectroscopy reveals a continuous hypsochromic shift of the emission peak from 543 nm to 519 nm (at 120 h) and 491 nm (at 1152 h), governed by subtractive water-driven etching and enhanced quantum confinement. This self-encapsulation framework provides a robust solution to halide perovskite instability in polar media.

We investigate ballistic electron transport through a one-dimensional Rashba quantum ring coupled to two quantum point contacts and driven by an off-resonant high-frequency electric field. Based on the Floquet effective Hamiltonian and the scattering matrix formalism, we propose an all-optical spin modulator that operates without external magnetic fields. We demonstrate that the synergy between Floquet engineering and the resonant geometry of the ring enables a full spin-flip transition at significantly reduced driving intensities. This resonant amplification provides an efficient alternative to traditional spin-control methods. Analytical conditions for the transmission peaks are derived, showing that the high-frequency field acts as an ``optical flux'' that can double the spin conductance magnitude compared to conventional magnetic tuning. Our findings establish the Floquet-Rashba ring as a scalable, intensity-efficient building block for next-generation spintronic circuits. Notably, while the core spin-modulating and switching features operate efficiently at zero external magnetic field, we show that a weak static magnetic flux can be employed as a complementary diagnostic tool to tune and map the coexisting Floquet, geometric, and Aharonov-Bohm interference phases.

It has been shown that a one-dimensional quantum ring with an asymmetric (mutually perpendicular) contact arrangement exposed to a nonresonance terahertz pulse serves as an optical spin gate modulator operating in a zero magnetic field. The implementation of a dynamic (optically controlled) analogue of the Datta–Das spin field-effect transistor with ferromagnetic contacts, which ensures ultrafast contactless control of the spin channel conductivity, has been demonstrated using the Floquet–Magnus expansion. The proposed circuit opens new prospects for the creation of coherent terahertz spintronic logic devices.

A model for a nuclear molecule composed of two heavy nuclei is proposed. To this end, the Hamiltonian of the dinuclear system is derived and diagonalized within a basis of bipolar spherical harmonics. Approximate analytical expressions describing the excitations of highly deformed molecular states are obtained. A remarkable agreement between numerical and analytical results is demonstrated in the description of low-energy roto-vibrational excitations in $^{240}$Pu. Furthermore, we provide predictions for the spectrum of hyperdeformed states in $^{232}$Th, treating it as a nuclear molecule consisting of $^{132}$Sn and $^{100}$Zr fragments. Finally, the angular distribution of fission fragments for $^{240}$Pu is analyzed and found to be in good agreement with available experimental data.

Halide perovskites (HPs) and their derivatives are emerging as a prominent class of materials for ionizing radiation detection.

Equilibrium configurations of one-component charge particles confined in a disk potential are analyzed at zero temperatures. With the increase of the particle number the hexagonal structure of equilibrium configurations breaks, giving rise to the nucleation of defects. One of the central issues is to identify conditions for the nucleation of the hexatic phase in such systems, which is accompanied by the appearance of defects in the Wigner crystalline phase. A joint orientation-translational correlation analysis of structural changes, occurring with an increase of the number of particles, elucidates the precursors of the onset of the hexatic phase in the considered system.

Transport of ballistic electrons through a 1D-dimensional quantum ring (subjected to Rashba spin–orbit interaction), connected with two external leads, is studied in the presence of external fields. These fields include the optical radiation, produced by an off-resonant high-frequency electric field, and a perpendicular magnetic field. With the aid of the Floquet theory, the key role of the interplay between the optical radiation intensity and the Rashba interaction is established for spin filtering effect of an initially arbitrary polarized electron beam at zero and low magnetic fields.

Boron nitride quantum dots combine several unique properties, including chemical stability, biocompatibility, and low cytotoxicity. These properties and tunable optical characteristics make them promising for the use in boron neutron capture therapy simultaneously as therapeutic agents and fluorescent markers for cancer cells. In this paper we present a case study, in which the electronic structure of these dots are analyzed within the DFT and TD-DFT methods providing a deeper understanding of the their absorption properties. Our approach enables an assessment of the overall effect of solvents on the absorption properties of these dots obtained by the solvothermal method. We show that solvents being medium for synthesis of quantum dots, actively participate in the formation of their absorption properties. It is demonstrated theoretically and experimentally that the change in optical properties is caused by the direct attachment of solvent molecules to the quantum dot surface.

We show that nanoparticles consisting of a boron-containing core and metallic shell layer can be designed to produce a strong absorption that gives rise to a plasmon resonance in the near infrared wavelength region. This feature, based on Fano resonance phenomenon, allows to invoke such nanoshells for fluorescence enhancement of boron-containing nanoparticles to be used as markers in tumor cells. The closed-form expression for asymmetric resonance in a nanoshell is derived in the dipole approximation.