Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum tricritical point emerging in the spin-boson model with two
  dissipative spins in staggered biases   We study the spin-boson model (SBM) with two spins in staggered biases by a
numerically exact method based on variational matrix product states. Several
observables such as the magnetization, the entanglement entropy between the two
spins and the bosonic environment, the ground-state energy, as well as the
correlation function for two spins are calculated exactly. The characteristics
of these observables suggest that the staggered biases can drive the 2nd-order
quantum phase transition (QPT) to the 1st-order QPT in the sub-Ohmic SBM, while
the Kosterlitz-Thouless QPT in the Ohmic SBM goes directly to the 1st-order
one. A quantum tricritical point, where the continuous QPT meets the 1st-order
one, can then be detected. It is found that the staggered biases would not
change the universality of { the phase transition in this model} below the
quantum tricritical point.

27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph
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The categories of this paper are: q-fin