| 摘 要： | The quantum phase transition(QPT) and quantum criticality of an anisotropic spin-1/2 XY chain under the interplay of magnetic field and Dzyaloshinskii–Moriya(DM) interaction, which is interpreted as an electric field, are investigated, wherein the anisotropic parameter plays a similar role as the superconducting pairing gap in the interacting Kitaev topological superconductor model that protects the topological order. It is shown that the thermal Drude weight is a good quantity to characterize the gapped(D_(th) = 0) and gapless(D_(th) 0) ground states. The continuous QPT is marked by a quantum critical point(QCP) associated with entropy accumulation, which is manifested by a characteristic Güneisen ratio(GR) with or without selfduality symmetry. It is shown that at a self-dual QCP, the GR keeps a finite value as T→0,while at a general QCP without self-duality symmetry, it displays a power-law temperature dependent divergence: Γ(T,r_c)～±T~(-1),which provides a novel thermodynamic means for probing QPT.
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