Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Anisotropic putative "up-up-down" magnetic structure in EuTAl$_4$Si$_2$
  (T = Rh and Ir)   We present detailed investigations in single crystals of two recently
reported quaternary intermetallic compounds EuRhAl$_4$Si$_2$ and
EuIrAl$_4$Si$_2$ employing magnetization, electrical resistivity in zero and
applied fields, heat capacity and $^{151}$Eu M\"{o}ssbauer spectroscopy
measurements. The two compounds order antiferromagnetically at $T_{\rm N1}$ =
11.7 and 14.7\,K, respectively, each undergoing two magnetic transitions: the
first from paramagnetic to incommensurate modulated antiferromagnetic, the
second at lower temperature to a commensurate antiferromagnetic phase as
confirmed by heat capacity and M\"{o}ssbauer spectra. The magnetic properties
in the ordered state present a large anisotropy despite Eu$^{2+}$ being an
$S$-state ion for which the single-ion anisotropy is expected to be weak. Two
features in the magnetization measured along the $c$-axis are prominent. At
1.8\,K, a ferromagnetic-like jump occurs at very low field to a value one third
of the saturation magnetization (1/3 M$_0$) followed by a wide plateau up to
2\,T for T = Rh and 4\,T for T = Ir. At this field value, a sharp hysteretic
spin-flop transition occurs to a fully saturated state (M$_0$). Surprisingly,
the magnetization does not return to origin when the field is reduced to zero
in the return cycle, as expected in an antiferromagnet. Instead, a remnant
magnetization 1/3 M$_0$ is observed and the magnetic loop around the origin
shows hysteresis. This suggests that the zero field magnetic structure has a
ferromagnetic component, and we present a model with up to third neighbor
exchange and dipolar interaction which reproduces the magnetization curves and
hints to an "up-up-down" magnetic structure in zero field.

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The categories of this paper are: hep-ph
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph