Emergence of the topological Hall effect in a tetragonal compensated ferrimagnet Mn2.3Pd0.7Ga

Topological spin textures such as magnetic skyrmions have attracted considerable interest due to their potential application in spintronic devices. However, there still remain several challenges to overcome before their practical application, for instance, achieving high scalability and thermal stability. Recent experiments have proposed a new class of skyrmion materials in the Heusler family, Mn1.4Pt0.9Pd0.1Sn and Mn2Rh0.95Ir0.05Sn, which possess noncollinear magnetic structures. Motivated by these experimental results, we suggest another Heusler compound hosted by Mn3Ga to overcome the above limitations. We fabricate Mn3-xPdxGa thin films, focusing on the magnetic compensation point. In Mn2.3Pd0.7Ga, we find a spin-reorientation transition around TSR = 320 K. Below the TSR, we observe the topological Hall effect and a positive magnetic entropy change, which are the hallmarks of a chiral noncollinear spin texture. By integrating all the data, we determine the magnetic phase diagram, displaying a wide chiral noncollinear spin phase even at room temperature. We believe that this compensated ferrimagnet shows promise for opening a new avenue toward chiral spin-based, high-density, and low-power devices.

Scalar compensation of shipboard three-component magnetic measurements and applications for marine geophysical mapping

<p>Since the 70’s, ship-mounted three-component magnetometers are used for marine geophysical mapping, with the benefits of being able to be operated permanently with a minimum of technical maintenance. However, to obtain accuracies similar to those of ship-towed absolute scalar magnetometers, the intense interfering magnetic fields generated by the hull and steel parts of the ship have to be removed. The most common correction method, called “vector compensation”, uses high precision inertial navigation systems in order to correct the measured data for the ship’s magnetic field and calculate the vector of the compensated magnetic field in the Earth coordinated system.</p><p>This work alternatively uses the “scalar compensation” method applied in airborne magnetism since the 60’s. The aim is to compute the intensity of the compensated magnetic field without measurements of the attitude of the vector and using linear least-square regression analysis. This correction method is applied to shipboard three-component magnetometer data acquired on different vessels during different surveys. Results are compared to those obtained with ship-towed absolute scalar magnetic measurements.</p><p><strong>Keywords</strong>: shipboard three-component magnetic measurements; magnetic compensation; marine magnetics.</p>

Distinctive exchange bias and unusual memory effects in magnetically compensated Pr0.75Gd0.25ScGe

Inter-lanthanide interactions in a distinctly layered lattice lead to magnetic compensation, exchange bias, and magnetic memory effects.