相关论文: Thermal entanglement in the nanotubular system Na_…
The present work reports an experimental observation of thermal entanglement in a clusterized spin chain formed in the compound Na$_2$Cu$_5$Si$_4$O$_{14}$. The presence of entanglement was investigated through two measured quantities, an…
We show that if the ground state entanglement exceeds the total entropy of a given system, then this system is in an entangled state. This is a universal entanglement witness that applies to any physical system and yields a temperature…
We show that macroscopic thermodynamical properties - such as functions of internal energy and magnetization - can detect quantum entanglement in solids at nonzero temperatures in the thermodynamical limit. We identify the parameter regions…
Based on the Hubbard model in the framework of non-phonon kinematical mechanism and taking into account the discreetness of an electronic energy spectrum, the superconducting critical temperature of a mesoscopic high-$T_{c}$ sphere is…
We demonstrate that the presence of entanglement in macroscopic bodies (e.g. solids) in thermodynamical equilibrium could be revealed by measuring heat-capacity. The idea is that if the system were in a separable state, then for certain…
Entanglement is a ubiquitous feature of low temperature systems and believed to be highly relevant for the dynamics of condensed matter properties and quantum computation even at higher temperatures. The experimental certification of this…
We show that magnetic susceptibility can reveal spin entanglement between individual constituents of a solid, while magnetisation describes their local properties. We then show that these two thermodynamical quantities satisfy complementary…
The entanglement in a general mixed spin chain with arbitrary spin $S$ and 1/2 is investigated in the thermodynamical limit. The entanglement is witnessed by the magnetic susceptibility which decides a characteristic temperature for an…
We study the thermal entanglement of a 2-qutrit spin chain with nonlinear coupling in the presence of nonuniform magnetic field. Thermal entanglement of an arbitrary (finite dimensional) m-partite system vanishes at some finite threshold…
Monte Carlo simulations of the magnetization temperature dependence in $D\times L$ nanotubes (periodic lateral boundary conditions) and nanostrips (free lateral boundary conditions) with $D$=8, 16, 32, 64$\ll L\longrightarrow 5000$ have…
We show that the thermal entanglement in a spin system using only magnetic susceptibility measurements is restricted to the insulator materials. We develop a generalization of the thermal entanglement witness that allows us to get…
This work investigates a system of three entangled qubits within the XXX model, subjected to an external magnetic field in the $z$-direction and incorporating an anisotropy term along the $y$-axis. We explore the thermodynamics of the…
We present a general argument showing that the temperature as well as other thermodynamical state variables can qualify as entanglement witnesses for spatial entanglement. This holds for a variety of systems and we exemplify our ideas using…
We demonstrate that the magnetic susceptibility of strongly alternating antiferromagnetic spin-1/2 chains is an entanglement witness. Specifically, magnetic susceptibility of copper nitrate (CN) measured in 1963 (Berger et al., Phys. Rev.…
Entanglement between individual spins can be detected by using thermodynamics quantities as entanglement witnesses. This applies to collective spins also, provided that their internal degrees of freedom are frozen, as in the limit of…
We examine the entanglement of thermal states of n spins interacting through different types of XY couplings in the presence of a magnetic field, by evaluating the negativities of all possible bipartite partitions of the whole system and of…
From experimental observations of limiting temperatures in heavy ion collisions we derive Tc, the critical temperature of infinite nuclear matter. The critical temperature is 16.6 +- 0.86 MeV. Theoretical model correlations between Tc, the…
We demonstrate how quantum entanglement can be directly witnessed in the quasi-1D Heisenberg antiferromagnet KCuF$_3$. We apply three entanglement witnesses --- one-tangle, two-tangle, and quantum Fisher information --- to its inelastic…
The 3D Ising-like system in the external field is described using the non-perturbative collective variables method. The universal as well as nonuniversal system characteristics are obtained within the framework of this approach. The…
We demonstrate that inelastic neutron scattering technique can be used to indirectly detect and measure the macroscopic quantum correlations quantified by both entanglement and discord in a quantum magnetic material, VODPO4 . 1D2O. The…