Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superconductor-insulator transition in fcc-GeSb2Te4 at elevated
  pressures   We show that polycrystalline GeSb2Te4 in the fcc phase (f-GST), which is an
insulator at low temperature at ambient pressure, becomes a superconductor at
elevated pressures. Our study of the superconductor to insulator transition
versus pressure at low temperatures reveals a second order quantum phase
transition with linear scaling (critical exponent close to unity) of the
transition temperature with the pressure above the critical zero-temperature
pressure. In addition, we demonstrate that at higher pressures the f-GST goes
through a structural phase transition via amorphization to bcc GST (b-GST),
which also become superconducting. We also find that the pressure regime where
an inhomogeneous mixture of amorphous and b-GST exists, there is an anomalous
peak in magnetoresistance, and suggest an explanation for this anomaly.

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The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex