相关论文: Staggered magnetization and entanglement enhanceme…
We study the entanglement emergence in a dipolar-coupled nuclear spin-1/2 system cooled using the adiabatic demagnetization technique. The unexpected behavior of entanglement for the next- and next-next-neighbor spins is revealed: entangled…
We investigate macroscopic entanglement in an infinite XX spin-1/2 chain with staggered magnetic field, B_l=B+e^{-i\pi l}b. Using single-site entropy and by constructing an entanglement witness, we search for the existence of entanglement…
We consider the entanglement in a two dimensional XY model in an external magnetic field h. The model consists of a set of 7 localized spin-1/2 particles in a two dimensional triangular lattice coupled through nearest neighbor exchange…
We study impurity effects in the spin nematic phase of the $S=1/2$ $J_1$-$J_2$ frustrated spin chain under an external magnetic field by using the infinite density matrix renormalization group and the bosonization. It is found that local…
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…
A relation between entanglement and criticality of spin chains is established. The entanglement we exploit is shared between auxiliary particles, which are isolated from each other, but are coupled to the same critical spin-1/2 chain. We…
We study how two magnetic impurities embedded in a solid can be entangled by an injected electron scattering between them and by subsequent measurement of the electron's state. We start by investigating an ideal case where only the…
We study effect of inhomogeneities of the lattice in the S=1/2 bond-alternating chain by using a quantum Monte Carlo method and an exact diagonalization method. We adopt a defect in the alternating order as the inhomogeneity and we call it…
The magnetic behavior of antiferromagnetic spin 1/2 chains with site-centered impurities in a magnetic field is investigated. The effect of impurities is implemented by considering different situations of both diagonal and off-diagonal…
We study the effect of anisotropy of spin-$S$ impurities on an antiferromagnetic SU(2) Heisenberg chain. The magnetic impurities are assumed to have an XXZ-type anisotropic exchange with its neighboring sites. First, using density-matrix…
We show that the entanglement between two distant magnetic impurities, generated via electron scattering, can be easily modulated by controlling the magnitude of an applied external electric field. We assume that the two magnetic impurities…
We study the effect of impurities on the two types of spin-dimers in the hybrid chain/ladder spin 1/2 quantum magnet Sr$_{14}$Cu$_{24}$O$_{41}$. Four different impurities were used, namely, the non-magnetic Zn (0.0025 and 0.01 per Cu) and…
The entanglement in one-dimensional random XY spin systems where the impurities of exchange couplings and the external magnetic fields are considered as random variables is investigated by solving the different spin-spin correlation…
A system consisting of two neutral spin 1/2 particles is analyzed for two magnetic field perturbations: 1) an inhomogeneous magnetic field over all space, and 2) external fields over a half space containing only one of the particles. The…
Using the bosonization technique, we have studied a spin-1/2 magnetic impurity in Heisenberg chain, and shown that the impurity specific heat and spin susceptibility have an anomalous temperature dependence.
We present a model where two magnetic impurities in a discrete tight-binding ring become entangled because of scattering processes associated to the injection of a conduction electron. We introduce a weak coupling approximation that allows…
The effects of boundary impurities on the entanglement entropy in an antiferromagnetic Heisenberg opened spin-$1/2$ chain are investigated. The method of density-matrix renormalization-group is used to obtain the bipartite entanglement. The…
We study the entanglement of magnetic impurities in an environment of electrons through successive scattering while an external magnetic field is applied. We show that the dynamics of the problem can be approximately described by a reduced…
We investigate the physics of a magnetic impurity with spin 1/2 in a correlated metallic host. Describing the band by a Hubbard Hamiltonian, the problem is analyzed using dynamical mean-field-theory in combination with Wilson's…
In the theory of dilute magnetic impurities in superconductors, the effect of all impurity spin-components is expressed via a single magnetic scattering rate $\Gamma_\mathrm{m}$. In a more realistic setting, magnetic impurities are…