Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ferromagnetic Quantum Criticality in the Quasi-One-Dimensional Heavy
  Fermion Metal YbNi4P2   We present a new Kondo-lattice system, YbNi4P2, which is a clean
heavy-fermion metal with a severely reduced ferromagnetic ordering temperature
at T_C=0.17K, evidenced by distinct anomalies in susceptibility, specific-heat,
and resistivity measurements. The ferromagnetic nature of the transition, with
only a small ordered moment of ~0.05mu_B, is established by a diverging
susceptibility at T_C with huge absolute values in the ferromagnetically
ordered state, severely reduced by small magnetic fields. Furthermore, YbNi4P2
is a stoichiometric system with a quasi-one-dimensional crystal and electronic
structure and strong correlation effects which dominate the low temperature
properties. This is reflected by a stronger-than-logarithmically diverging
Sommerfeld coefficient and a linear-in-T resistivity above T_C which cannot be
explained by any current theoretical predictions. These exciting
characteristics are unique among all correlated electron systems and make this
an interesting material for further in-depth investigations.

10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an