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arXiv · 0811.3419

Entanglement and level crossings in frustrated ferromagnetic rings

Masudul Haque·V. Ravi Chandra·Jayendra N. Bandyopadhyay
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Abstract

We study the entanglement content of a class of mesoscopic tunable magnetic systems. The systems are closed finite spin-1/2 chains with ferromagnetic nearest-neighbor interactions frustrated by antiferromagnetic next-nearest-neighbor interactions. The finite chains display a series of level crossings reflecting the incommensurate physics of the corresponding infinite-size chain. We present dramatic entanglement signatures characterizing these unusual level crossings. We focus on multi-spin and global measures of entanglement rather than only one-spin or two-spin entanglements. We compare and contrast the information obtained from these measures to that obtained from traditional condensed matter measures such as correlation functions.

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Masudul Haque, V. Ravi Chandra, Jayendra N. Bandyopadhyay. 2008-11-20. Entanglement and level crossings in frustrated ferromagnetic rings. https://doi.org/10.1103/physreva.79.042317

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