Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dipolar Interactions and Origin of Spin Ice in Ising Pyrochlore Magnets   Recent experiments suggest that the Ising pyrochlore magnets ${\rm
Ho_{2}Ti_{2}O_{7}}$ and ${\rm Dy_{2}Ti_{2}O_{7}}$ display qualitative
properties of the spin ice model proposed by Harris {\it et al.} \prl {\bf 79},
2554 (1997). We discuss the dipolar energy scale present in both these
materials and consider how they can display spin ice behavior {\it despite} the
presence of long range interactions. Specifically, we present numerical
simulations and a mean field analysis of pyrochlore Ising systems in the
presence of nearest neighbor exchange and long range dipolar interactions. We
find that two possible phases can occur, a long range ordered antiferromagnetic
one and the other dominated by spin ice features. Our quantitative theory is in
very good agreement with experimental data on both ${\rm Ho_{2}Ti_{2}O_{7}}$
and ${\rm Dy_{2}Ti_{2}O_{7}}$. We suggest that the nearest neighbor exchange in
${\rm Dy_{2}Ti_{2}O_{7}}$ is {\it antiferromagnetic} and that spin ice behavior
is induced by long range dipolar interactions.

26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph