Abstract
Using the trace minimization algorithm, we carried out an exact calculation of entanglement in a 19-site two-dimensional transverse Ising model. This model consists of a set of localized spin- particles in a two-dimensional triangular lattice coupled through exchange interaction and subject to an external magnetic field of strength . We demonstrate, for such a class of two-dimensional magnetic systems, that entanglement can be controlled and tuned by varying the parameter in the Hamiltonian and by introducing impurities into the systems. Examining the derivative of the concurrence as a function of shows that the system exhibits a quantum phase transition at about , a transition induced by quantum fluctuations at the absolute zero of temperature.
6 More- Received 22 September 2009
DOI:https://doi.org/10.1103/PhysRevA.81.022324
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