Investigation of the structure and dielectric properties of doped barium titanates

This work examined the influence of zirconium concentration on barium titanate (BZT) BaZrxTi1-xO3, with (x = 0, 0.15, 0.50, 0.75, and 1), produced by the tartrate precursor technique. The Fourier transform infrared (FTIR) spectra support the X-ray diffraction (XRD) results regarding formation of the perovskite structure. Grain size grows with Zr concentration, suggesting that the presence of Zr ions enlarges the grains. The transmission electron microscopy (TEM) images demonstrated that, due to their nano size, nanocrystallites are agglomerated in most images with irregular morphologies and average particle sizes from 20.75 nm to 63.75 nm. Increasing Zr content diminished the piezoelectric coefficient (d33) and the grain size. The value of d33 decreases by increasing Zr content, and there is an inverse relationship between grain size and d33. The remnant polarization of BZT increases with increasing Zr4+ content, which may be suitable for permanent memory device applications.

Crystal structure and peculiarities of microwave parameters of Co1-xNixFe2O4 nano spinel ferrites

Nanosized spinel ferrites Co1-xNixFe2O4 (where x = 0.0-1.0) or CNFO have been produced using a chemical method. The crystal structure's characteristics have been determined through the utilization of X-ray diffraction (XRD). It has been demonstrated that all samples have a single phase with cubic syngony (space group Fd3̄m). The lattice parameter and unit cell volume behavior correlate well with the average ionic radii of Co2+ and Ni2+ ions and their coordination numbers. Thus, an increase in the Ni2+ content from x = 0.0 to x = 1.0 leads to a decrease in the lattice parameter (from 8.3805 to 8.3316 Å) and unit cell volume (from 58.86 to 57.83 Å3). Elastic properties have been investigated using Fourier transform infrared (FTIR) analysis. The peculiarities of the microwave properties have been analyzed by the measured S-parameters in the range of 8-18 GHz. It was assumed that the energy losses due to reflection are a combination of electrical and magnetic losses due to polarization processes (dipole polarization) and magnetization reversal processes in the region of inter-resonant processes. A significant attenuation of the reflected wave energy (-10 … -21.8 dB) opens broad prospects for practical applications.

Generalized Toffoli Gate Decomposition Using Ququints: Towards Realizing Grover's Algorithm with Qudits

Qubits, which are the quantum counterparts of classical bits, are used as basic information units for quantum information processing, whereas underlying physical information carriers, e.g., (artificial) atoms or ions, admit encoding of more complex multilevel states-qudits. Recently, significant attention has been paid to the idea of using qudit encoding as a way for further scaling quantum processors. In this work, we present an efficient decomposition of the generalized Toffoli gate on five-level quantum systems-so-called ququints-that use ququints' space as the space of two qubits with a joint ancillary state. The basic two-qubit operation we use is a version of the controlled-phase gate. The proposed N-qubit Toffoli gate decomposition has O(N) asymptotic depth and does not use ancillary qubits. We then apply our results for Grover's algorithm, where we indicate on the sizable advantage of using the qudit-based approach with the proposed decomposition in comparison to the standard qubit case. We expect that our results are applicable for quantum processors based on various physical platforms, such as trapped ions, neutral atoms, protonic systems, superconducting circuits, and others.