Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum phase transition in the heavy-fermion compound YbIr$_2$Si$_2$   We investigate the pressure-temperature phase diagram of YbIr$_2$Si$_2$ by
measuring the electrical resistivity $\rho(T)$. In contrast to the widely
investigated YbRh$_2$Si$_2$, YbIr$_2$Si$_2$ is a paramagnetic metal below
$p_c\simeq 8$ GPa. Interestingly, a first-order, presumably ferromagnetic,
transition develops at $p_c$. Similar magnetic properties were also observed in
YbRh$_2$Si$_2$ and YbCu$_2$Si$_2$ at sufficiently high pressures, suggesting a
uniform picture for these Yb compounds. The ground state of YbIr$_2$Si$_2$
under pressure can be described by Landau Fermi-liquid (LFL) theory, in
agreement with the nearly ferromagnetic Fermi-liquid (NFFL) model. Moreover,
evidence of a weak valence transition, characterized by a jump of the
Kadowaki-Woods (KW) ratio as well as an enhancement of the residual resistivity
$\rho_0$ and of the quasiparticle-quasiparticle scattering cross section, is
observed around 6 GPa.

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The categories of this paper are: q-alg
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph