Magnetic Polarity Research Articles

Sub-nanosecond magnetic vortex reversal induced by localized resonant strain field in doped nanomagnets

The strain-induced magnetic vortex dynamics in nanomagnets with ring-shaped impurities are investigated by means of micromagnetic simulations. It is found that the type and location of impurities can modulate the strain-stimulated spin wave spectrum of the magnetic vortex. Compared with pure nanomagnets without doping, the scattering impurities make the eigenfrequency of nanomagnets higher, while the pinning impurities lead to lower eigenfrequency. Moreover, the spin wave oscillation amplitude in a doped nanomagnet is strengthened by the gradient of exchange energy at the interface between the impurity ring and nanomagnet. The magnetic vortex polarity in a nanomagnet with specific doping schemes can be reversed in a sub-nanosecond scale by a localized resonant strain signal. Besides the switching efficiency improvement, the threshold stress of sub-nanosecond polarity reversal in nanomagnets with specific doping schemes is also reduced compared to the counterpart of nanomagnets without impurities. These results indicate that doping engineering of nanomagnets is a significant method to achieve straintronic devices with higher operating frequency and lower energy consumption.

Physical Compensation Approach for Feature Enhancement of High-Speed MFL Signals via Magnetic Field Polarization

Physical Compensation Approach for Feature Enhancement of High-Speed MFL Signals via Magnetic Field Polarization

Structural, magnetic and transport properties of FeRuVZ (Z = Si, Ge) Heusler alloys: Experiment and theory

Heusler alloys based on 4d-elements are relatively less explored though they are known to host interesting electronic/magnetic properties useful for future spintronics applications. Here, we report a comparative study of the structural and magnetic properties of FeRuVSi (FRVS) and FeRuVGe (FRVG) using experimental and theoretical tools. Magneto-transport measurements have also been carried out to probe the role of magnetism on their transport behaviour. Room temperature (T) X-ray diffraction data reveals cubic crystal structure (space group No. 216) with B2 type antisite disorder between Fe and Ru sites in both the alloys. They show ferromagnetic behaviour below the Curie temperature (TC) 84 K for FeRuVSi and 57 K for FeRuVGe respectively. The field dependence of magnetization at low-T shows saturating (nearly saturating) behaviour for FRVS (FRVG). Transport measurements show metallic behaviour with a sharp reduction in the resistivity near TC. Ab-initio calculations predict nearly half metallic behaviour with ∼ 87 % and ∼ 89 % spin polarization for FRVS and FRVG in their ordered states. The inclusion of antisite disorder changes the magnetic configuration, leading to a visible decrease in the magnetic moment and spin polarization. The calculated net moment and the transport properties agree fairly well with those observed experimentally. These results confirm the importance of disorder in determining the intrinsic properties of these alloys. Such combined studies help in the identification of more novel quantum materials suitable for future spintronic applications.

Low-Loss Buried InGaAs/InP Integrated Waveguides in the Long-Wave Infrared.

In this work, we present a photonic integrated platform based on buried InGaAs waveguides with InP cladding that operates over a large mid-infrared (mid-IR) spectral range. Thanks to wet-etch fabrication patterning and Fe doping, low propagation losses below 1.2 dB/cm (0.3 cm-1 loss coefficient) have been obtained between 4.6 and 11.2 μm wavelengths (890-1960 cm-1 wavenumber), in both transverse electric (TE) and transverse magnetic (TM) polarization modes. The possibility of monolithically integrating such waveguides with mid-IR sources offers promising perspectives for developing broadband, homogeneously integrated systems.

U-Pb calcite ages date oblique rifting of the Arctic–North Atlantic gateway

Abstract Miocene breakup of Svalbard from Greenland formed a deep oceanic gateway that enabled circulation between the Arctic and Atlantic Oceans, significantly changing the global climate. However, the timing of events remains unclear. An excellent opportunity to constrain this timing is found onshore western Svalbard, where the Sarsbukta fault forms the eastern margin of the Eocene–Oligocene Forlandsundet basin. Here, we present new results from U-Pb dating of calcite precipitated in fault-related veins to constrain the timing of Sarsbukta fault deformation and the evolution of the basin. Our oldest calcite age is Permo-Triassic, suggesting long-lived deformation along the fault. A cluster of ages between 41 and 33 Ma overlaps with fossil-based depositional ages from parts of the Forlandsundet basin. These data indicate that onshore transtension partly pre-dated the well-established Chron 13 (magnetic polarity time scale; 35.5–33.7 Ma) reorganization of spreading ridges in the North Atlantic. Our youngest age of 13 Ma indicates that faulting persisted long after the preserved basin fill was deposited. If seafloor spreading marked the end of extension of continental crust, Molloy Ridge spreading during Chron 5 (19.6–9.8 Ma) may have initiated after 13 Ma.

Design of TE-polarized resonant Bessel-beam launchers for wireless power transfer links in the radiative near-field region

Abstract Resonant Bessel-beam launchers (BBLs)are radiating devices constituted by a cylindrical metallic cavity with a partially reflecting sheet (PRS) on top. Millimeter-wave resonant BBLs typically exhibit transverse magnetic (TM) polarization due to the use of coaxial probes as feeders and homogenized metasurfaces as PRS. Launchers showing either a purely transverse electric (TE) or a hybrid (quasi-TE) polarization have recently been proposed for realizing wireless power transfer (WPT) links in the radiative near-field region at millimeter waves. The former are obtained by means of a radial slot array as a feeder and a homogenized metasurface as a PRS. The latter are obtained by using a loop antenna as a feeder and an annular strip grating in the homogenization limit as radiating aperture. In this work, based on an original semi-analytical model, such a metasurface is demonstrated to show a dichroic behavior. This interpretation explains the improvement in terms of polarization purity with respect to more nondichroic conventional homogenized metasurfaces. The behavior of the annular strip grating under a pure TM polarization is tested with a coaxial feeder, whereas its behavior under a pure TE polarization is tested by means of the radial slot array feeder. Results confirm the validity of the proposed analysis, which is finally exploited to evaluate the WPT performance.

The effect of different transition metal dopants on the magnetic properties of armchair antimonene, phosphorene, and their binary nanoribbons

Binary antimonene-phosphorene, a novel two-dimensional material with a medium band gap, high carrier mobility, and environmental stability, has attracted growing attention due to its wide applications in spintronics. Using density functional theory, we comprehensively investigate and compare the structural and magnetic properties of armchair Sb, P, and binary SbP nanoribbons doped with 3d transition metal atoms (Ti, Cr, Mn, Fe, Co, and Ni) with various concentrations of dopant atoms. We investigated magnetic properties, including magnetic moment, spin polarization, and spin density. It was found that the magnetic properties for single P and Sb nanoribbons do not depend on the substitution position of TM atoms. In contrast, for binary SbP nanoribbons, the substitution of TM atoms in P or Sb positions leads to different behaviors. For example, the magnetization for substitution of Fe and Co atoms in the P position of the binary SbP nanoribbon will be greater than those of the Sb position, but for other impurity atoms, the magnetization of the binary SbP nanoribbon does not strongly depend on the substitution position. The results show that with increasing the number of impurity atoms in the nanoribbon, the magnetic moment increases, except for the nickel atom in the Sb position of the SbP nanoribbon, in which the nanoribbon prefers the ferrimagnetic state. Also, the spin density results show that the magnetism of the doped systems is mainly attributed to the dopant atoms, and the neighboring atoms have a negligible contribution. The findings of antimonene-phosphorene nanoribbons doped with TM atoms may have potential applications in spintronic nanodevices.

Optical and fluorescent properties in Er, Yb:YAG double-line waveguide by femtosecond laser direct writing

This paper reports the double-line waveguides in Er,Yb:YAG prepared by femtosecond laser (fs-laser) writing at 1030 nm, 450 fs pulse and 100 kHz repetition rate. When light propagates at 632.8 nm along transverse electric (TE) and transverse magnetic (TM) polarization, efficient single-mode guidance is demonstrated in the double-line structures. The minimum transmission loss is as low as 0.98 dB/cm in waveguide with space of 18 μm. The structural modifications in damaged tracks and strain-affected regions were characterized by confocal micro-Raman spectroscopy, and the refractive index variations were analyzed. The corresponding fluorescence emissions of Er3+ and Yb3+ are investigated in the Er,Yb:YAG double-line structure.

Magnetic polarity stratigraphy of quaternary sediments from Ramganga paleolake, NW Himalaya, India and its paleoenvironmental implications

Paleomagnetic records from the sediments provide the foundation for studying variations in the geomagnetic field across the geological time sacle. Here, we report a new paleomagnetic data from Quaternary sediments of Ramganga Paleolake, NW Himalaya, India, to provide more insight into the global geomagnetic excursions and paleoenvironmental implications. Paleomagnetic and rock magnetic analyses were performed on a 5 m thick vertical profile of unconsolidated sediments from the Ramganga paleolake (29°46′867″N; 79°14′043″E), located in the Lesser Himalaya at a height of 798 m. One hundred fifty oriented samples from 50 sites (10 cm intervals) were obtained from the vertical section. Extrapolating the optically stimulated luminescence (OSL) dates from literature indicates that the entire section was probably deposited between 38 and 0.8 ka. The rock magnetic data shows that the remanence is carried by a low coercivity mineral and a significant amount of a soft magnetic mineral, most likely magnetite. Virtual Geomagnetic Pole (VGP) latitudes were calculated. Plot of the VGP latitudes against the sample locations from the litho-column allows us for the construction of Magnetic Polarity Stratigraphy (MPS) column. The MPS of the Ramganga paleolake has detected three geomagnetic excursions that are correlated with the global events: the Mono Lake Event (∼28.4-25.8 ka), the Gulf of Mexico Event (∼12.5–17 ka), and the Bagwalipokar Excursion Events (15.5-14.7 ka and 8-2.85 ka) respectively. The lower and middle portion of the paleolake represents the low and high energy depositional environment during the sediment deposition due to wet and arid climatic conditions.

Design and analysis of polarization-insensitive molybdenum-based ultra-wideband solar energy absorber with wide-incident-angle

We introduce an ultra-wideband absorber with a molybdenum and Al2O3 multilayer structure for solar energy harvesting. The proposed structure could maintain its structural integrity at high temperatures thanks to the refractory materials used in its construction. Under normal incidence of optical waves, absorption of more than 90% is achieved throughout a broad range of wavelengths from 300 nm to approximately 3177 nm with a bandwidth of 2877 nm which covers ultraviolet, visible, and near-infrared spectral bands. The average absorption in that band is calculated to be 96.46%. The proposed design’s symmetrical characteristic makes the absorber insensitive to the polarization of the incident optical wave. Furthermore, throughout a broad range of optical wave angles of incidence for both transverse electric and transverse magnetic polarizations, the absorber supports absorptivity greater than 80%.

Large thermoelectric transport in magnetically coupled CrI3/1T-MoS2 vdW heterostructure via spin–charge interconversion

Low-dimensional materials with prominent thermoelectric (TE) effect play a pivotal role in realizing state-of-the-art nanoscale TE devices. The fusion of TE effect with the magnetism through seamless integration of TE and magnetic materials in the 2D limit offers access to control longitudinal as well as transverse TE properties via magnetic proximity effect. Herein, we design a van der Waals (vdW) heterostructure of metallic 1T-MoS2 with promising TE properties and a layer-dependent magnetic CrI3 material. The result highlights exotic electronic and magnetic configurations of the designed monolayer-CrI3/1T-MoS2 vdW heterostructure, which show magnetically-coupled TE characteristics. The observed remarkable magnetic proximity stems from large magnetic anisotropy energy and spin polarization, which are found to be 2.21 meV Cr−1 and 12.30%, respectively. To this end, the semiconducting CrI3 layer with intrinsic magnetism leads to efficient control and tunability of the observed spin-correlated anomalous Nernst effect. Moreover, a large dimensionless figure of merit of ∼6 and a power factor of ∼3.8×1011/τ∘ Wm−1K−2s−1 near the Fermi level at 300 K endorse the rejuvenated TE effect. The strong relativistic spin–orbit coupling validates the significant correlation of TE properties with intrinsic magnetic configuration. The present study underscores the significance of the magnetic proximity-governed TE effect in vdW heterostructures to engineer low-dimensional TE devices.

Fitting the light curves of Sagittarius A* with a hot-spot model

Context. Sagittarius A* (Sgr A*) exhibits frequent flaring activity across the electromagnetic spectrum. Signatures of an orbiting hot spot have been identified in the polarized millimeter wavelength light curves observed with ALMA in 2017 immediately after an X-ray flare. The nature of these hot spots remains uncertain. Aims. We expanded existing theoretical hot-spot models created to describe the Sgr A* polarized emission at millimeter wavelengths. We sampled the posterior space, identifying best-fitting parameters and characterizing uncertainties. Methods. Using the numerical radiative transfer code ipole, we defined a semi-analytical model describing a ball of plasma orbiting Sgr A*, threaded with a magnetic field and emitting synchrotron radiation. We then explored the posterior space in the Bayesian framework of dynesty. We fit the static background emission separately, using a radiatively inefficient accretion flow model. Results. We considered eight models with a varying level of complexity, distinguished by choices regarding dynamically important cooling, non-Keplerian motion, and magnetic field polarity. All models converge to realizations that fit the data, but one model without cooling, non-Keplerian motion, and magnetic field pointing toward us improved the fit significantly and also matched the observed circular polarization. Conclusions. Our models represent observational data well and allow testing various effects in a systematic manner. From our analysis, we have inferred an inclination of ∼155 − 160 deg, which corroborates previous estimates, a preferred period of ∼90 min, and an orbital radius of 9 − 12.0 gravitational radii. Our non-Keplerian models indicate a preference for an orbital velocity of 0.6–0.9 times the Keplerian value. Last, all our models agree on a high dimensionless spin value (a* > 0.8), but the impact of spin on the corresponding light curves is subdominant with respect to other parameters.

Rotationally symmetric transverse magnetic vector wave propagation for nonlinear optics

In this paper the theory and simulation results are presented for 3D cylindrical rotationally symmetric spatial soliton propagation in a nonlinear medium using a modified finite-difference time-domain general vector auxiliary differential equation method for transverse magnetic polarization. The theory of 3D rotationally symmetric spatial solitons is discussed, and compared with two (1 + 1)D, termed “2D” for this paper, hyperbolic secant spatial solitons, with a phase difference of π (antiphase). The simulated behavior of the 3D rotationally symmetric soliton was compared with the interaction of the two antiphase 2D solitons for different source hyperbolic secant separation distances. Lastly, we offer some possible explanations for the simulated soliton behavior.

Design of functionally gradient metastructure with ultra-broadband and strong absorption

Rational design principles for ultra-broadband lattice-based metastructure absorbers (MMAs) remain scarcely explored, including elucidation of the governing absorption phenomena. This work presents Octet truss lattices gradient-tailored to achieve highly efficient wide-spectrum electromagnetic (EM) wave mitigation. The optimized 15 mm thick three-dimensional printed architectures comprise three stacked sub-layers with graduated densities spanning a reflective backing. Analysis of unit cell EM responses as a function of geometric parameters facilitates concurrent broadband absorption and minimal mass. Consequently, ultra-wideband absorption below −10 dB persists from 2.84 to 40.0 GHz under normal incidence, with strongly enhanced attenuation below −15 dB between 8.51 and 40.0 GHz. Additionally, consistent absorption capacity endures up to 60° for both transverse electric (TE) and transverse magnetic (TM) polarizations, empowered by the intricate conductive networks established through wave interactions. The unique combination of additive manufacturing, hierarchical metamaterial engineering, and physical insights provides a versatile strategy for customized broadband absorption systems across application domains.

Hole-Doped Nonvolatile and Electrically Controllable Magnetism in van der Waals Ferroelectric Heterostructures

Electrical control of magnetism in van der Waals semiconductors is a promising step towards development of two-dimensional spintronic devices with ultralow power consumption for processing and storing information. Here, we propose a design for two-dimensional van der Waals heterostructures (vdWHs) that can host ferroelectricity and ferromagnetism simultaneously under hole doping. By contacting an InSe monolayer and forming an InSe/In2Se3 vdWH, the switchable built-in electric field from the reversible out-of-plane polarization enables robust control of the band alignment. Furthermore, switching between the two ferroelectric states (P ↑ and P ↓) of hole-doped In2Se3 with an external electric field can interchange the ON and OFF states of the nonvolatile magnetism. More interestingly, doping concentration and strain can effectively tune the magnetic moment and polarization energy. Therefore, this provides a platform for realizing multiferroics in ferroelectric heterostructures, showing great potential for use in nonvolatile memories and ferroelectric field-effect transistors.

Ultra-low loss compact active TM mode pass polarizer using phase change material in silicon waveguide

An active low-loss transverse magnetic (TM) pass polarizer, based on the phase change material (Ge2Sb2Te5), is proposed. The proposed polarizer is based on silicon-on-insulator technology that consists of a silicon waveguide that incorporates a thin layer of Si3N4 placed in-between GST. Enhancing the interaction between light and GST is achieved by strategically placing a double-layer GST adjacent to the slot waveguide. The polarizer’s tunability, on the other hand, depends on the shift in the refractive index (RI) of GST as it transitions between its crystalline and amorphous phases. By optimizing the structure, the polarizer exhibits negligible loss for both modes in the amorphous phase, and with the change of phase to crystalline, the loss of TE mode is more than 8 dB. In contrast, the loss of TM is less than 0.05 dB with a high ER of 21.82 dB, propagation length of 79.89 µm and Figure of merit reaches up to 108 at 1550 nm. Due to the combination of these performance parameters, the suggested active TM pass polarizer is an appealing and effective device for various photonic applications. In addition, the fabrication technique of the proposed active TM pass polarizer is explained.

Quantum mechanical modeling of high-intensity laser pulse interaction with hydrogen atom with considering the magnetic field and polarization

In the study of the non-relativistic interaction between high-intensity femtosecond laser pulses and atoms, the influence of the magnetic field is commonly overlooked. This work investigates the effects of the magnetic field in the high-intensity few-cycle laser pulses with non-relativistic intensity of 3.5×1014W/cm2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$3.5 \ imes 10^{14} { }\\;\\;{\ ext{W}}/{\ ext{cm}}^{2}$$\\end{document} at the center wavelength of 800 nm on the high-order harmonic generation (HHG), attosecond pulse train (APT), isolated attosecond pulse (IAP), and the electron trajectory in the hydrogen atom, employing the numerical solution of the time-dependent Schrödinger equation in three dimensions (3D-TDSE). Two polarizations, linear and circular, are considered. A comparison with the scenario where the magnetic field is not considered shows that the magnetic field can apply significant corrections to the results. Particularly, considering the magnetic field for circular polarization can make the cutoff frequency of HHG coincide with the semi-classical relationship of ħωc=Ip+3.17Up\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbar {\\upomega }_{{\ ext{c}}} = {\ ext{I}}_{{\ ext{p}}} + 3.17{\ ext{U}}_{{\ ext{p}}}$$\\end{document}, a case that for circular polarization does not exist without considering the magnetic field. Moreover, accounting for the magnetic field leads to a reduction in the attosecond pulse duration for circular polarization for APT (360as\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$360{\ ext{ as}}$$\\end{document} versus 241as\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$241{\ ext{ as}}$$\\end{document}) and for IAP (834as\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$834{\ ext{ as}}$$\\end{document} versus 602as\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$602{\ ext{ as}}$$\\end{document}). Additionally, the difference in production efficiency of HHG and APT between linear and circular polarization is reduced by two orders of magnitude, when magnetic field is considered. Although considering the magnetic field complicates the electron trajectory, especially for circular polarization, however, our quantum model provides enhanced insight into how the interaction works, especially when and where the electron collides with the parent nucleus. In this case, the quantum mechanical modeling largely covers the huge difference of not considering the magnetic field in the results predicted by other works.

Magnetostratigraphy of the Late Cretaceous to Early Eocene sediments from the Tulsipur section, western Nepal: Tectonic implications for the Indian northern passive margin

The sedimentary strata from the Late Cretaceous to Early Eocene in the Himalayan foothills offer detailed insights into land collision processes. Unfortunately, a comprehensive dating study on these strata has been lacking, limiting our understanding of the collision and splicing history of the Indian and Lhasa plates. To address this question, we conducted a paleomagnetic study on the Late Cretaceous to Early Eocene succession in the Tulsipur area, western Nepal. The paleomagnetic data obtained from a 357 m thick succession were used to establish a new magnetostratigraphic framework for this region. The observed magnetic polarity sequence contains six normal and six reversed polarity zones, spanning the age range of 68–54 Ma (Maastrichtian to Early Eocene). In addition, two major and two stable sediment accumulation rates (SARs) were identified which were likely controlled by tectonics. The rifting and subsidence events caused by continuous northward movement of the Indian plate might have modulated the shifting of distal offshore to tidal flat settings in this region. We document fifteen (Unit I) and seven (Unit II) transgressive-regressive cycles, indicative of passive margin instability influenced by near-field effects of the India-Asian convergence. This new magnetostratigraphic result is expected to serve as a basic age framework in reconstructing the Late Mesozoic and Early Cenozoic tectonic evolution. Furthermore, it will also facilitate reliable cross-regional correlation between lithostratigraphic units across passive margins in the southern Himalaya and similar strata in the Tethyan Himalaya and active continental margins of the southern Tibetan Plateau.

A wide-angle broadband dual-polarization electromagnetic absorbing structure based on the carbonyl iron powder/polydimethylsiloxane composites

Electromagnetic absorbing structure with wide-angle and broadband absorption plays a vital role in radar stealth. Hence, a novel gradient composite multilayer absorbing structure (GCMAS) is designed and fabricated by a simple and low-cost direct ink writing (DIW) 3D printing technology. The GCMAS consists of the CIP/PDMS composites composed of carbonyl iron powder (CIP) and polydimethylsiloxane (PDMS), which have outstanding flexibility, chemical and thermal stability. By metastructure design of gradient composites, a material-structure–function integrated absorbing structure with 50 wt% CIP/PDMS in the top layer, 60 wt% CIP/PDMS in the middle two layers, and 70 wt% CIP/PDMS in the bottom two layers is obtained. Simulations demonstrate that the designed GCMAS with the thickness of 13 mm can achieve the −10 dB absorbing bandwidth in the frequency range from 2.88 to 38.24 GHz, and the absorbing bandwidth corresponding to −15 dB in 2.97–36.17 GHz. The maximum reflection loss is −42.17 dB at 22.96 GHz. Experiments demonstrate that the GCMAS can achieve the −10 dB absorbing bandwidth in 3.6–40 GHz. Moreover, the GCMAS also can maintain the broadband and strong absorbing performance with incident angle from 0° to 50° for transverse electric (TE) polarization and 0° to 60° for transverse magnetic (TM) polarization. This work provides a promising strategy for the fabrication of functional gradient composites and flexible or bendable absorbing structure, which have great potential in satellite communications and radar stealth.

Broadband high-contrast-grating-type waveplates for the terahertz range

The high-contrast-grating waveplates utilizing high contrast between silicon and air refractive indexes were developed in order to perform as a quarter wave and a half wave plate in the selected THz frequency range. The waveplates possessed anti-reflective properties due to the specific inclination of the walls both in parallel and in perpendicular direction to grating axis, efficiently suppressing the reflection losses caused by air-dielectric interface for both transverse magnetic and transverse electric polarizations. Moreover, significant reduction of the transmittance gap was achieved between both polarizations while mitigating overall Fabry-Perot effect. Validation of the concepts was carried out by measuring transmission amplitude and phase spectra of the fabricated samples in a broadband of THz time-domain spectroscopy and vector-network-analysis systems considering also some real applications.