International Journal of Quantum Information

PURE STATE ENTANGLEMENT BETWEEN SEPARATED REGIONS USING IMPENETRABLE BOSONS

Javier Molina-Vilaplana, Sougato Bose, V. E. Korepin

Published Jul 1, 2008• 3 citations

Abstract

We study a way of establishing a pure entangled state between two segments of a 1D ring using impenetrable bosons. The two bosons are initially simply placed at two positions on the ring which is an unentangled state. After some time evolution, we project the segments to a pure state through coarse grained measurements which ascertain whether there is a particle present in a given segment without revealing any information about its position within the segment. Subject to finding a particle in each segment, we quantify the entanglement established between the segments through the von Neumann entropy of a subsystem. We also investigate whether this entanglement increases with the number of particles and compare the entanglement in dynamical and ground states.

DOI: 10.1142/s0219749908004043

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