2,859 research outputs found
Critical behaviors near the (tri-)critical end point of QCD within the NJL model
We investigate the dynamical chiral symmetry breaking and its restoration at
finite density and temperature within the two-flavor Nambu-Jona-Lasinio model,
and mainly focus on the critical behaviors near the critical end point (CEP)
and tricritical point (TCP) of quantum chromodynamics. The multi-solution
region of the Nambu and Wigner ones is determined in the phase diagram for the
massive and massless current quark, respectively. We use the various
susceptibilities to locate the CEP/TCP and then extract the critical exponents
near them. Our calculations reveal that the various susceptibilities share the
same critical behaviors for the physical current quark mass, while they show
different features in the chiral limit
Quantum Discord for Investigating Quantum Correlations without Entanglement in Solids
Quantum systems unfold diversified correlations which have no classical
counterparts. These quantum correlations have various different facets. Quantum
entanglement, as the most well known measure of quantum correlations, plays
essential roles in quantum information processing. However, it has recently
been pointed out that quantum entanglement cannot describe all the
nonclassicality in the correlations. Thus the study of quantum correlations in
separable states attracts widely attentions. Herein, we experimentally
investigate the quantum correlations of separable thermal states in terms of
quantum discord. The sudden change of quantum discord is observed, which
captures ambiguously the critical point associated with the behavior of
Hamiltonian. Our results display the potential applications of quantum
correlations in studying the fundamental properties of quantum system, such as
quantum criticality of non-zero temperature.Comment: 4 pages, 4 figure
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