Magnetic interactions and high-field magnetotransport properties of Ge1--Sn Mn Te epitaxial layers

In this work, we present the structural, magnetic and magnetotransport results of Ge1−x−ySnxMnyTe thin layers with × = 0.076–0.22 and y = 0.051–0.16. The samples were grown via molecular beam epitaxy with thickness ranging from 160 nm to 900 nm. From X-ray diffraction analysis, the layers maintain low symmetry rhombohedral crystal structure inherited from the host lattice. The rhombohedral distortion is well-maintained in doped layer even up to the highest Sn and Mn contents, x ≈ 0.22 and y ≈ 0.051. The dc magnetic susceptibility, χdc(T) of all three layers manifests large bifurcation in the field-cooled/zero-field-cooled curves which might represent frustrated magnetic state interpreted as possible cluster-glass order. From high field magnetotransport results, a negative to positive crossover in magnetoresistance is observed for y = 0.11 at T ≈ 36 K. Furthermore, we also present a modified scaling results of anomalous Hall resistivity which displays a large magnitude, ρAH ≈ 4.9 μΩcm at T = 4.3 K for the layer with y = 0.11. The scaling results show that both skew scattering and side-jump mechanisms contribute to the anomalous Hall effect in Ge1−x−ySnxMnyTe samples however; the later seems to be dominant driving mechanism.