Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pressure-enhanced superconductivity in Eu$_3$Bi$_2$S$_4$F$_4$   The pressure effect on the newly discovered charge-transferred BiS$_2$-based
superconductor, Eu$_3$Bi$_2$S$_4$F$_4$, with a $T_c$ of 1.5 K at ambient
pressure, is investigated by transport and magnetic measurements. Accompanied
with the enhancement of metallicity under pressures, the onset superconducting
transition temperature increases abruptly around 1.0 GPa, reaching $\sim$10.0 K
at 2.26 GPa. AC magnetic susceptibility measurements indicate that a new
superconducting phase with a higher $T_c$ emerges and dominates at high
pressures. In the broad pressure window of 0.68 GPa$\leq$$p$$\leq$2.00 GPa, the
high-$T_c$ phase coexists with the low-$T_c$ phase. Hall effect measurements
reveal a significant difference in electronic structures between the two
superconducting phases. Our work devotes the effort to establish the
commonality of pressure effect on the BiS$_2$-based superconductors, and also
uncovers the importance of electron carrier density in the high-$T_c$ phase.

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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
16
The categories of this paper are: stat
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The categories of this paper are: patt-sol
18
The categories of this paper are: econ
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The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
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The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
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The categories of this paper are: ao-sci
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin