Half-metallic ferromagnetic (HMF) materials show high spin polarization and are therefore interesting to researchers due their possible applications in spintronic devices. In these materials, while one sub band has a finite density of states at the Fermi level, other gap. Because Curie temperature (TC) tunable electronic structure, HMF Heusler alloys have special importance among materials. Full with stoichiometric composition X2YZ (where X Y transition metals Z is sp element) cubic L21...

In this paper, we report the signature of spin gapless semiconductor (SGS) in CoFeMnSi that belongs to Heusler family. SGS is a new class magnetic semiconductors which have band gap for one subband and zero other, thus are useful tunable transport based applications. We show various experimental evidences behavior by carefully carrying out spin-polarization measurements. also confirmed first-principles band-structure calculations. The most stable configuration obtained theoretical...

Despite a plethora of materials suggested for spintronic applications, new class has emerged, namely spin gapless semiconductors (SGS), which offers potentially more advantageous properties than existing ones. These magnetic exhibit finite band gap one channel and closed the other. Here, supported by electronic-structure calculations, we report evidence SGS behavior in equiatomic quaternary CoFeCrGa, having cubic Heusler (prototype LiMgPdSn) structure but exhibiting chemical disorder...

We report the structure, magnetic property and spin polarization of CoFeMnGe equiatomic quaternary Heusler alloy. The alloy was found to exist in L21 structure with considerable amount DO3 disorder. Thermal analysis result indicated Curie temperature is about 711K without any other phase transformation up melting temperature. magnetization value close that predicted by Slater-Pauling curve. Current P = 0.70 {plus/minus}0.1 deduced using point contact Andreev reflection (PCAR) measurements....

Abstract The unique electronic properties of topological quantum materials, such as protected surface states and exotic quasiparticles, can provide an out-of-plane spin-polarized current needed for external field-free magnetization switching magnets with perpendicular magnetic anisotropy. Conventional spin–orbit torque (SOT) materials only in-plane current, recently explored lower crystal symmetries very low components, which are not suitable energy-efficient SOT applications. Here, we...

We report the structural and magnetic properties of CoFeMnSi equiatomic quaternary Heusler alloy thin films. The epitaxial growth single-crystalline films with full $B2$ partial $L{2}_{1}$ ordering on Cr-buffered MgO(001) substrate was achieved using in situ postannealing at temperature (${T}_{\mathrm{a}}$) $500\ensuremath{-}600{\phantom{\rule{0.16em}{0ex}}}^{\ensuremath{\circ}}\mathrm{C}$. A saturation magnetization value about...

Tunnel magnetoresistance (TMR) in MgO-based magnetic tunnel junctions (MTJs) with equiatomic quaternary CoFeMnSi Heusler and CoFe alloy electrodes is studied. The epitaxial MTJ stacking structures were prepared using ultrahigh-vacuum magnetron sputtering, where the electrode has a full B2 partial L21 ordering crystal structure. Maximum TMR ratios of 101% 521% observed at room temperature 10 K, respectively, for MTJs. large bias voltage dependence ratio was also low (LT), as similarly Co2MnSi...

Spin-gapless semiconductors (SGSs) are new states of quantum matter, which characterized by a unique spin-polarized band structure. Unlike conventional or half-metallic ferromagnets, they carry finite bandgap for one spin channel and close (zero) gap the other thus useful tunable transport applications. It is latest classes materials considered spintronic devices. A few several advantages SGS include (i) high Curie temperature, (ii) minimal amount energy required to excite electrons from...

We investigate a W-Ta alloying route to reduce the auto-oscillation threshold current densities and power consumption of nanoconstriction based spin Hall nano-oscillators. Using spin-torque ferromagnetic resonance measurements on microbars ${\mathrm{W}}_{100\ensuremath{-}x}{\mathrm{Ta}}_{x}$(5 nm)/$\mathrm{Co}$-$\mathrm{Fe}$-$\mathrm{B}$($t$)/$\mathrm{Mg}\mathrm{O}$ stacks with $t=1.4$, 1.8, 2.0 nm, we measure substantial improvement in both spin-orbit torque efficiency conductivity....

Spin gapless semiconductors (SGSs) are an interesting class of materials which bridge the gap between and half-metallic ferromagnets. This shows band in one spin channels a zero other, thus promote tunable transport. Here, we present structural, electronic, magnetic, transport properties Co-rich SGS ${\mathrm{Co}}_{1+x}{\mathrm{Fe}}_{1\ensuremath{-}x}\mathrm{CrGa}$ using both theoretical experimental techniques. The key advantage samples...

Ferromagnetic materials dominate as the magnetically active element in spintronic devices, but come with drawbacks such large stray fields, and low operational frequencies. Compensated ferrimagnets provide an alternative they combine ultrafast magnetization dynamics of antiferromagnets a ferromagnet-like spin-orbit-torque (SOT) behavior. However to use devices their advantageous properties must be retained also ultrathin films (t < 10 nm). In this study, ferrimagnetic Gdx(Fe87.5Co12.5)1-x...

While mutually interacting spin Hall nano-oscillators (SHNOs) hold great promise for wireless communication, neural networks, neuromorphic computing, and Ising machines, the highest number of synchronized SHNOs remains limited to $N$ = 64. Using ultra-narrow 10 20-nm nano-constrictions in W-Ta/CoFeB/MgO trilayers, we demonstrate SHNO networks up 105,000. The microwave power quality factor scale as with new record values 9 nW $1.04 \times 10^6$, respectively. An unexpectedly strong array size...

Abstract Current-induced magnetization switching is demonstrated in a micron sized Hall bar consisting of Pt-capped ultrathin ferrimagnetic MnGa films. The films showed low M s ≃ 150 kA/m and large perpendicular magnetic anisotropy (PMA) field <?CDATA $\mu _{0}H_{K}^{\text{eff}} \simeq 2.5$?> T, indicating PMA thickness t product $K_{\text{u}}^{\text{eff}}t 0.47$?> mJ/m 2 , which relatively larger than those reported for other material with PMA. Magnetization induced by an in-plane...

Spin Hall nano-oscillators (SHNOs) are emerging spintronic oscillators with significant potential for technological applications, including microwave signal generation, and unconventional computing. Despite their promising SHNOs face various challenges, such as high energy consumption difficulties in growing high-quality thin film heterostructures clean interfaces. Here, single-layer topological magnetic Weyl semimetals open a possible solution they possess both intrinsic ferromagnetism...

Magnetic materials with low Gilbert damping and magnetization are necessary for the realization of faster or more energy-efficient spintronic devices based on spin-transfer-torque. Here, we report in epitaxially grown equiatomic quaternary CoFeMnSi Heusler alloy films. The 10 nm-thick films show a saturation M S = 630 emu cm−3 constant , which relatively small values among transition metal ferromagnets, addition to its soft magnetic properties. physical origin possibility further reduction α...

Perpendicular magnetic tunnel junctions (p-MTJs) with a MgO barrier and 1-nm-thick MnGa electrode were investigated by inserting several monolayers (MLs) of Mn. The magnetoresistance (TMR) ratio systematically increased when increasing the Mn layer thickness maximum 18 (38.4)% at 300 (5) K for 0.6–0.8 nm. This is five times higher compared to that without layer. perpendicular anisotropy (PMA) field PMA constant ultrathin also up 62–90 kOe 6.2–11.3 Merg/cm3, respectively, an increase in...

A detailed study of the Fe2 − xCoxMnSi (0 ≤ x 0.6) alloys has been carried out by investigating samples x-ray diffraction, Mössbauer spectroscopy, magnetization, transport and current spin polarization measurements. perfectly ordered L21 phase is found to exist for = 0.4. Competing magnetic interactions between ferromagnetic antiferromagnetic (AFM) phases are seen in with < 0.2, whereas AFM completely absent ≥ 0.2 as revealed magnetization resistivity data. The Curie temperature saturation...

Nano-constriction based spin Hall nano-oscillators (SHNOs) are at the forefront of spintronics research for emerging technological applications, such as oscillator-based neuromorphic computing and Ising Machines. However, their miniaturization to sub-50 nm width regime results in poor scaling threshold current. Here, it shows that current shunting through Si substrate is origin this problem studies how different seed layers can mitigate it. It finds an ultra-thin Al

Van der Waals (vdW) magnets are promising, because of their tunable magnetic properties with doping or alloy composition, where the strength interactions, symmetry, and anisotropy can be tuned according to desired application. However, so far, most vdW magnet-based spintronic devices have been limited cryogenic temperatures anisotropies favoring out-of-plane canted orientation magnetization. Here, we report beyond room-temperature lateral spin-valve strong in-plane magnetization spin...

The equiatomic quaternary Heusler alloy CoFeCrAl is a candidate material for spin-gapless semiconductors (SGSs). However, to date, there have been no experimental attempts at fabricating junction device. This paper reports fully epitaxial (001)-oriented MgO barrier magnetic tunnel (MTJ) with electrodes grown on Cr buffer. X-ray and electron diffraction measurements show that the (001) electrode films atomically flat surfaces $B2$-ordered phase. saturation magnetization 380 emu/cm$^3$, almost...