Orthogonal Phase Research Articles

New Transformation Pathway of cg-N from HeN4 under Moderate Pressure

A new transformation pathway from HeN4 to cg-N is proposed. The structure search method reveals orthorhombic phase P212121-HeN4. An orthogonal phase o-N is formed after the element He moves away from the channel of the N-structure. o-N is found to maintain its structural configuration when the pressure is decreased to 40 GPa. Interestingly, further decreasing the pressure to 35 GPa results in the transformation of o-N to cg-N. Detailed structural evolution behaviors of P212121-HeN4 and o-N with the decreased pressure are ascertained to understand the mechanism of the structural transformation. The P212121-HeN4 phase and the o-N phase exhibit high energy density and prominent detonation properties (detonation pressure and detonation velocity), which make them potential candidates for applications in high energy density materials.

Generalized Bessel Gaussian vortex in the turbulent media of absorbing seawater

We investigate the effects of turbulent absorbing seawater and generalized Bessel Gaussian (GBG) vortex structural parameters on the transmission of orbital angular momentum (OAM). The receiving probability spectrum and bit error probability of OAM mode carried by GBG vortex are deduced with the orthogonal spiral phase expansion of random GBG vortex and signal-to-noise ratio of OAM mode. By numerical analysis, the underwater transmission invariance of GBG vortex is studied, and the optimal aperture angle of GBG vortex corresponding to the maximum received probability of OAM signal is obtained. The impact of seawater parameters and optical transceiver systems on bit error probability is analyzed by using optimal aperture angle. We found that the transmission invariance of OAM modes of GBG vortex is well maintained even in weak turbulent absorbing seawater. Moreover, received probability and bit error probability are significantly affected even if the deviation of the aperture angle from its optimal position is minimal, and Durnin-ring radius should be the minimum within the experimental allowable range. According to signal transmission distance, the selection of high SNR transceiver system, optimal aperture angle, low order OAM topological charge, and minimum Durnin-ring radius allowed by the experiment can optimize the OAM signal transmission efficiency.

Circularly polarized edge‐placed printed monopole antenna using theory of characteristic modes

AbstractThis article presents a method of using modal analysis to characterize the circular polarization (CP) performance of a printed monopole antenna. The radiator and feedline are positioned on the edge of the substrate and fed accordingly at the edge, and a modified ground plane is employed. The complete antenna without excitation is analyzed using characteristic mode theory to provide physical insight into its CP operation. The modal analysis proves that several nearly orthogonal modes can be generated at certain frequencies with orthogonal phase differences as well. The axial ratio (AR) corresponds to the modal analysis which proves the validity of the modal analysis. An axial ratio bandwidth from 3.1 to 6.2 GHz (66. 7%) is achieved within an S11 bandwidth of 2.6–11 GHz (123.5%). The proposed antenna is compact with stable radiation patterns, easy to design, and fabricate without inserting parasitic patches or inserting slots on the antenna.

High sideband suppression silicon single sideband modulator integrated with a radio frequency branch line coupler

We demonstrate a single-chip silicon optical single sideband (OSSB) modulator composed of a radio frequency (RF) branch line coupler (BLC) and a silicon dual-parallel Mach–Zehnder modulator (DP-MZM). A co-design between the BLC and the DP-MZM is implemented to improve the sideband suppression ratio (SSR). The modulator has a modulation efficiency of V π L π ∼ 1.75 V · cm and a 3 dB electro-optical (EO) bandwidth of 48.7 GHz. The BLC can generate a pair of RF signals with equal amplitudes and orthogonal phases at the optimal frequency of 21 GHz. We prove through theoretical calculation and experiment that, although the BLC’s performance in terms of power balance and phase orthogonality deteriorates in a wider frequency range, high SSRs can be realized by adjusting relevant bias phases of the DP-MZM. With this technique, the undesired sidebands are completely suppressed below the noise floor in the frequency range from 15 GHz to 30 GHz when the chip operates in the full carrier OSSB (FC-OSSB) mode. In addition, an SSR > 35 dB and an carrier suppression ratio (CSR) > 42 dB are demonstrated at 21 GHz in the suppressed carrier OSSB (SC-OSSB) mode.

Generation of Square Optical Vortex Array and Optical Helix Array by Periodic Orthogonal Binary Phase Plate

Generation of Square Optical Vortex Array and Optical Helix Array by Periodic Orthogonal Binary Phase Plate

Interaction between spatial perception and temporal perception enables preservation of cause-effect relationship: Visual psychophysics and neuronal dynamics.

Visual perception of moving objects is integral to our day-to-day life, integrating visual spatial and temporal perception. Most research studies have focused on finding the brain regions activated during motion perception. However, an empirically validated general mathematical model is required to understand the modulation of the motion perception. Here, we develop a mathematical formulation of the modulation of the perception of a moving object due to a change in speed, under the formulation of the invariance of causality. We formulated the perception of a moving object as the coordinate transformation from a retinotopic space onto perceptual space and derived a quantitative relationship between spatiotemporal coordinates. To validate our model, we undertook the analysis of two experiments: (i) the perceived length of the moving arc, and (ii) the perceived time while observing moving stimuli. We performed a magnetic resonance imaging (MRI) tractography investigation of subjects to demarcate the anatomical correlation of the modulation of the perception of moving objects. Our theoretical model shows that the interaction between visual-spatial and temporal perception, during the perception of moving object is described by coupled linear equations; and experimental observations validate our model. We observed that cerebral area V5 may be an anatomical correlate for this interaction. The physiological basis of interaction is shown by a Lotka-Volterra system delineating interplay between acetylcholine and dopamine neurotransmitters, whose concentrations vary periodically with the orthogonal phase shift between them, occurring at the axodendritic synapse of complex cells at area V5. Under the invariance of causality in the representation of events in retinotopic space and perceptual space, the speed modulates the perception of a moving object. This modulation may be due to variations of the tuning properties of complex cells at area V5 due to the dynamic interaction between acetylcholine and dopamine. Our analysis is the first significant study, to our knowledge, that establishes a mathematical linkage between motion perception and causality invariance.

Study on Collinear Holographic Storage System with Orthogonal Phase Encryption

Study on Collinear Holographic Storage System with Orthogonal Phase Encryption

Defect Evolution in Y<sub>0.5</sub>Gd<sub>0.5</sub>Ba<sub>2</sub>Cu<sub>3</sub>O<sub>7-</sub><sub>δ</sub> Layer by H Ion Irradiation

In order to further improve the superconducting current carrying capacity of REBCO coated conductor under strong magnetic field, ion irradiation is used to generate the pinning center of introduced magnetic flux in the REBCO coated conductor. In this paper, the H-ion irradiation of REBCO second generation high temperature superconductor strip was carried out by using the 320kV high charge state ion synthesis research platform. DB-SPBA combined with Raman spectroscopy was used to measure the change of microstructure in YBCO samples irradiated by H+ions within the range of 5.0×10<sup>14</sup>~1.0×10<sup>16</sup>. The positron annihilation parameters in YBCO before and after irradiation were analyzed. It is found that after 100 keV H+ion irradiation, a large number of defects including vacancy, vacancy group or dislocation group are produced in the superconducting layer. The larger the irradiation dose, the more vacancy type defects are produced, the more complex the defect types are, and the annihilation mechanism of positrons in the defects changes. Raman spectroscopy results show that with the increase of H+ion irradiation dose, the oxygen atoms in the coating rearrange, the plane spacing increases, the orthogonal phase structure of the coating is destroyed, and the degree of order decreases. The defects produced by such ion irradiation lay a foundation for the introduction of flux pinning centers. Further research can be carried out in combination with X-ray diffractometer, transmission electron microscope, superconductivity and other testing methods to provide theoretical and practical reference for the optimization of material properties.

UNICODE AS AN ANALOGUE OF THE GENCODE

The structure of artificial intelligence as a multilevel symmetry is built by association with natural intelligence, being its digitized analogue. The principle of reduction of multivalent truth values is formulated. A metaphysical clock with two hands describing two levels of genesis, which consists of orthogonal phases of the rhythm of becoming, is constructed. There is an easy way to directly comprehend the truth. These are two level coordinates based on a Cartesian square.

A Fiber-Optic Extrinsic Fabry–Perot Hydrophone Based on Archimedes Spiral-Type Sensitive Diaphragm

A fiber-optic hydrophone based on extrinsic Fabry–Perot (F-P) interferometer is proposed. The sensitive element of the hydrophone is an Archimedes spiral metal diaphragm, and the inner surface of the diaphragm and the end face of the optical fiber form the F-P cavity. Due to the grooved surface of the sensitive diaphragm, the hydrophone is minimally affected by hydrostatic pressure. The geometry structure of sensor and finite element method (FEM) modeling is presented. Experiments of underwater acoustic response and sensitivity calibration of the hydrophone are carried out and the experimental phase results are demodulated by the orthogonal phase demodulation method based on birefringent crystals and polarization technology. The experiment results show that the hydrophone has a relatively flat signal-to-noise ratio (SNR) and sensitivity within 1–20 kHz, and the average sensitivity is −172.52 dB (re. 1 rad/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> Pa) @ 1–20 kHz. We believe that this type of hydrophone has the potential to be applied in the field of underwater acoustic communication.

Effect of Mn Doping on the Microstructure and Electrical Properties of Potassium Niobate Ceramics Using Plasma Spraying

KNN piezoelectric ceramics are of great importance in the field of scientific research due to their high Curie temperature, good electrical properties, etc. The application of potassium sodium niobate K0.5Na0.5NbO3 (KNN) is strictly limited due to the volatility of Na+ and K+ in KNN and its leakage current. In order to investigate the effect of Mn doping on KNN-based piezoelectric ceramic coatings, KNN and KNN-0.02Mn (KNMN) coatings were successfully prepared using a plasma spraying technique. The phase structure, microscopic morphology, and electrical properties of the coatings were studied in the research. The results showed that both the KNN and KNMN coatings had chalcogenide structures. The KNN coating had an orthogonal phase structure, whereas the KNMN coating had a tetragonal phase structure. Compared with the KNN coating, the microhardness of the KNMN coating was improved through doping with Mn ions. The doping of Mn ions could replace both the A and B sites in the KNN piezoelectric ceramics, further reducing the oxygen vacancies and leakage currents in the coating, and its dielectric properties were improved.

Improvement of Ferroelectricity in Ce-Doped Hf0.5Zr0.5O2 Thin Films

At present, ion doping is a popular method typically used to regulate the ferroelectric properties of Hf0.5Zr0.5O2 films. In this work, Ce (cerium)–doped Hf0.5Zr0.5O2 (Ce: HZO) films on Pt/TiN/SiO2/Si substrates were prepared by the chemical solution deposition (CSD) method. The microstructure and ferroelectric properties of the Ce–doped HZO films were investigated in detail. The experimental results showed that the remanent polarization value of the films with cerium doping concentration of 7 mol% reached 17 μC/cm2, which is a significant improvement compared with the undoped Hf0.5Zr0.5O2 films. The reason for this may be the introduction of cerium ions, which can introduce a certain number of oxygen vacancies, thus stabilizing the formation of the orthogonal phase. Interestingly, the films were shown to be nearly fatigue free after 109 cycles of testing. These results demonstrate that cerium ion doping is an effective method for stabilizing the formation of the orthogonal phase of HZO films, and improving the ferroelectricity of HZO thin films.

Branched medium-chain fatty acid profiling and enantiomer separation of anteiso-forms of teicoplanin fatty acyl side chain RS3 using UHPLC-MS/MS with polysaccharide columns

This work reports on targeted UHPLC-tandem mass spectrometry methods for the chiral separation of anteiso-methyl branched fatty acids (aiFAs). The methods involve precolumn derivatization with 1-naphthylamine and chiral separation on Chiralpak IG-U. anteiso-Methyl branched fatty acids with up to eight carbons can be separated. A method was used for the assignment of the absolute configuration of an aiFA present as fatty acyl residue of the teicoplanin mixture, namely teicoplanin RS3. Furthermore, the excellent methylene selectivity and improved selectivity for constitutional isomers of the polysaccharide columns was exploited for the elucidation and structural confirmation of previously unknown fatty acyl residues in teicoplanin. This shows the versatility and practical applicability of polysaccharide columns as orthogonal stationary phases to reversed-phase for structural elucidation of natural compounds. The developed methods are useful tools for related subdisciplines such as targeted metabolomics and lipidomics.

Influence of the molecular structure of calamitic compounds with trifluoromethoxy terminal group on the induction of the smectic a phase. Part I

ABSTRACT For the liquid crystalline mixtures of compounds with positive and negative dielectric anisotropies, the induction of the liquid crystal smectic A phase can be observed. This effect can be very favourable for definite specific purposes. The main aim of this work is to determine the influence of the molecular structure of compounds with a polar trifluoromethoxy (-OCF3) group on the induction strength of the orthogonal smectic A (SmA) phase. In order to reach this target, the phase diagrams of the mixtures were established using the polarised optical microscope observations. The presence of a triple bond, phenyl and cyclohexyl rings as well as fluorine atoms in the core and the length of terminal alkyl chains of the tested compounds were considered. The length of the rigid core has the greatest effect on the induction strength of the SmA phase, while the length of the alkyl chain (3–5 carbon atoms) has relatively minor influence. Explaining the correlation between the molecular structure and the induction strength, the dipole moments and the polarisability of the molecules should be taken into account. For shorter molecules, changes in the molecular structure have more significant influence on the temperature and concentration range of the orthogonal SmA phase.

Synthesis and photoluminescence properties of a novel green-emitting LiYGeO4 :Tb3+ long afterglow phosphor.

A new green luminescent phosphor, Li(Y1-x Tbx )GeO4 , was prepared using a high-temperature solid-phase method. The X-ray diffraction (XRD) measured spectrum agreed well with the standard card JCPDS No. 02-3479, indicating that it is a quaternary compound belonging to the space group of Pnma(62) with an orthogonal crystalline phase; the excitation and emission spectra measured using the phosphor spectrometer showed that it can be effectively excited by near-ultraviolet light at 378 nm and blue light at 482 nm, and produced excellent strong emission of green light at 550 nm. The afterglow test results show that the sample had a good long afterglow effect at lower doping concentrations; the thermal stability test results showed that its thermal burst activation energy ΔE ≈ 0.37 eV had its excellent thermal stability. The rare earth Tb3+ -doped green phosphor, LiYGeO4 :Tb3+ , has potential applications in household lighting, medical therapy, and optical storage.

Transport properties and phase diagrams of FeSe1−S (0 ≤ x ≤ 1) single crystals

Based on the high quality FeSe1−xSx (0 ≤ x ≤ 1) single crystals synthesized via a hydrothermal method, we carried out systematic measurement of the normal state magnetoresistance and Hall effect. Through the maximum entropy mobility spectrum analysis (MEMSA), we investigate the evolution of mobility spectrum, which reflects the multi-band structures for different doping content x and temperature T. The relationships between Tc and carrier properties calculated by MEMSA, as well as bond angles and anion height calculated by first-principle method are investigated. Nonlinear to linear transition of Hall resistivity(ρxy(B)) is mainly attributed to the decreasing mobilities and merging of mobility peaks with the reductive x or increasing T. The relationship between Tc and carrier density n show weak interaction for the orthogonal phases when x ≤ 0.2, but nearly positive correlation for the tetragonal phases when x > 0.2. Bond angle as well as the Se/S anion height change almost linearly with x within the tetragonal phases, and the V-shaped relationships with Tc indicate that structural factors play a key role in the regulation of superconductivity. Our researches are helpful for understanding the multi-band and complex phase diagram of iron-based superconductors.

Wake-Up Free La-Doped HfO2-ZrO2 Ferroelectrics Achieved With an Atomic Layer-Specific Doping Technique

In this letter, wake-up free La-doped HfO2-ZrO2 (HZO) ferroelectrics are experimentally fabricated using an atomic layer-specific doping (ALSD) technique, which selectively introduces La dopants at effective locations to facilitate the formation of ferroelectric orthorhombic phase. With this technique, robust La-doped HZO ferroelectric devices that are mostly free from the undesired wake-up effect and anti-ferroelectricity were demonstrated over a large La doping range (from 2.9 to 11.5%). Moreover, large remanent polarization and good endurance were achieved at the same time (>107 cycles). The outstanding performances can be attributed to the effective stabilization of ferroelectric orthogonal phase and the suppression of tetragonal phase, through controlling of the dopants’ local environment. Thus, ALSD is an effective approach to achieve reliable, wake-up free and CMOS-compatible HZO-based ferroelectrics.

Orthogonal phase mixing for improved linearity phase interpolator

As the demand for high-speed low-power transceivers grows, it is critical to have precise clock timing circuits such as phase interpolators (PI) that allow maximizing link margin. A linearization technique which optimizes linearity without increasing power and area is presented. Implemented in a 7-nm complimentary metal oxide silicon (CMOS) technology, PI achieves less than 0.5 integral non-linearity (INL) while consuming only 184 μA from a 0.75-V supply at 4.3 GHz.

Effects of Nb additions on the microstructure and tribological properties of Al0.25CrFeNi1.75 high-entropy alloy

The microstructure evolution and tribological properties of the Al0.25CrFeNi1.75Nbx (x is molar ratio, x = 0, 0.3, 0.6, 0.66, 0.69, 0.72 and 0.75, denoted by Nb0.3, Nb0.6, Nb0.66, Nb0.69, Nb0.72, and Nb0.75, respectively) high entropy alloys (HEAs) were investigated. The results indicated that the microstructure of Al0.25CrFeNi1.75Nbx was composed of orthogonal structure phase of AlCrNi type, Laves phase of FeCrNb type and tetragonal structure phase of AlNi3 type. These alloys shows superior hardness and promising wear resistance. When Nb (the molar ratio of Nb is 0.66) were introduced into Al0.25CrFeNi1.75 alloy, the alloy showed a low wear rate which was 4.2 ± 0.40 × 10−4 mm3 N−1 m−1, and the hardness reaches 727 HV. The research finding of hardness and tribological properties demonstrated that the addition of Nb can effectively improve the hardness and wear resistance of the Al0.25CrFeNi1.75 alloy.

Two-step orthogonalization phase demodulation method based on a single differential interferogram.

To reduce the acquisition time of interferogram and provide a dynamic phase retrieval method with arbitrary phase shift using a dual-channel simultaneous polarization phase-shifting system, a two-step orthogonalization phase demodulation method (TOPD) based on a single differential interferogram is proposed in this paper. In this method, the differential interferogram obtained by subtracting two phase-shifting interferograms and one of the Gaussian filtered based-interferograms are used to normalize and orthogonalize, and then the phase related parameters are solved by the Lissajous ellipse fitting method. Finally, the measured phase is obtained with high accuracy. The proposed method further reduces the deviation caused by the filtering operation performed in the two-step phase demodulation method. At the same time, combined it with the Lissajou ellipse fitting method reduces the limitation associated with the approximation conditions of the orthogonalization and normalization method. The experimental and simulation results demonstrate that this method provides a solution with high accuracy, high stability, strong practicability, and few restrictions for phase extraction in quantitative phase imaging.