Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Inverted hysteresis and negative remanence in a homogeneous
  antiferromagnet   Magnetic remanence - found in bar magnets or magnetic storage devices - is
probably the oldest and most ubiquitous phenomenon underpinning technological
applications of magnetism. It is a macroscopic non-equilibrium phenomenon: a
remanent magnetisation appears when a magnetic field is applied to an initially
unmagnetised ferromagnet, and then taken away. Here, we present an inverted
magnetic hysteresis loop in the pyrochlore compound Nd$_2$Hf$_2$O$_7$: the
remanent magnetisation points in a direction opposite to the applied field.
This phenomenon is exquisitely tunable as a function of the protocol in field
and temperature, and it is reproducible as in a quasi-equilibrium setting. We
account for this phenomenon in considerable detail in terms of the properties
of non-equilibrium population of domain walls which exhibit a magnetic moment
between domains of an ordered antiferromagnetic state which itself has zero net
magnetisation. Properties and (non-equilibrium) dynamics of topological defects
play an important role in modern spintronics, and our study adds an instance
where a uniform field couples selectively to domain walls rather than the bulk.

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The categories of this paper are: stat
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph