Search arXivSearch

arXiv · 2203.06960

Application of the point-like contact model: Resistance Oscillations of the Domain Wall in Magnetic Nanowires and Junctions due to Mean Free Path Effects

Abstract

This work is focused on determining the electrical resistance, which induced by single domain wall in magnetic nanowire with a negligible defect. The provided model covers a wide range of nanowire's diameters. The obtained result demonstrates a few orders rapid reduction of the domain wall resistance accompanied by its possible deviations versus the diameter growth ranging from 1.2 nm to 15.2 nm. The origin of these deviations, which are also identified as oscillations, is referred to the non-uniform electron scattering on the domain wall due to the intermixing electron scattering conditions: ballistic for one spin channel and quasi-ballistic for other one with opposite spin direction. It may happen when the domain wall width by value is approximately in between two lengths: a mean free path with the spin down and spin up. The indirect evidence of this finding is also coming from the fact that homogeneous nanowires shows the most valuable domain wall resistance oscillations by magnitude rather than segmented magnetic nanowires. In addition to the approach, where DW width is constant, the other reasonable model is used when the domain wall can be constrained for some conditions. The same results are valid for magnetic junctions with domain wall. Finally, resistance simulation in the diffusive range, when a diameter of the nanowire (or point-like junction) is larger than any of spin resolved mean free path of electrons, successfully follows experimental data for the single and double domain wall resistances available in literature.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Artur Useinov. 2022-03-14. Application of the point-like contact model: Resistance Oscillations of the Domain Wall in Magnetic Nanowires and Junctions due to Mean Free Path Effects. https://doi.org/10.1142/s2010-3247(21)50031-4

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

THz-Driven Quantum Ionic Magnetism in a Quantum Paraelectric SrTiO3

Magnetic moments carried by rotating ionic motion in crystals are becoming recognized as an important contribution to magnetism, angular momentum transport, and optical activity. However, efficient approaches to their dynamical control are lacking. Here, we report THz-driven generation and optical detection of quantum ionic magnetism in quantum paraelectric SrTiO3. We observe an oscillatory ionic magnetization without a corresponding oscillatory polarization, contradicting from the classical relation M~PXdP/dt while its suppression above the quantum paraelectric regime points to a quantum ionic origin. Analysis shows that this effect results from the beating between quantum ionic eigenstates whose degeneracy is lifted due to the directional symmetry breaking by the THz pulse. The presented approach provides a pathway for the ultrafast control of ionic magnetization in quantum materials for spintronic and thermotronic applications.

cond-mat.other

Matching Rules for a Three-Dimensional Strongly Aperiodic Monotile

A recent pre-print [arXiv:2609.19214] proposed a three-dimensional (3D) strongly aperiodic monotile: a shape that tiles Euclidean space only aperiodically and which admits no symmetry of infinite order. The proof takes the 3D Chair tile identified previously by Lee and Moody, and adds geometric decorations to the faces so as to force aperiodicity (without these decorations The Chair also admits periodic tilings). Here we establish general requirements on face decorations to achieve the same end, in order to facilitate the search for physical realisations. We find that the requirements are minimal. We provide matching rules using three colours of arrow. They are not equivalent to the original rules, but force the same tiling by forcing Chairs to compose into `Superchairs' with doubled linear dimensions. In this process the matching rules themselves compose uniquely, which is the core of the earlier proof. Relaxing this constraint further we find that the same structure can be forced using only a matching rule based on the colours of squares, regardless of orientation. Any physical system encoding these rules (geometrically or otherwise) will force the strongly aperiodic monotiling. We provide simple examples.

cond-mat.other

THz Spectroscopy of Urine Vapors from Patients with Prostate Cancer and Benign Prostatic Hyperplasia: A Pilot Analysis

Approximately 13% of men will be diagnosed with prostate cancer (PC) during their lifetime. Serum prostate-specific antigen (PSA) is widely used for screening and risk assessment; however, PSA elevations are not cancer-specific and may also occur in benign conditions such as prostatitis and benign prostatic hyperplasia (BPH). Additional non-invasive approaches capable of provid- ing complementary molecular information are therefore needed. Here, we present an exploratory pilot study using high-resolution terahertz (THz) spectroscopy to examine urine-derived volatile and thermal-decomposition products. Analysis of urine samples from 24 patients with PC and 14 patients with BPH identified differences in the reported molecular-assignment patterns and candi- date spectral features for further evaluation. The study was designed for candidate identification and feasibility assessment and did not evaluate diagnostic accuracy or superiority to PSA. These findings support further investigation of THz spectroscopy as a potential source of complementary molecular information alongside PSA and other established clinical assessments. The study also outlines the technical standardization and clinical-validation requirements that must be addressed before this approach can be considered for routine clinical use.

cond-mat.other