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arXiv · 0704.1718

Spin-spin Correlation in Some Excited States of Transverse Ising Model

Anjan Kumar Chandra·Subinay Dasgupta
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Abstract

We consider the transverse Ising model in one dimension with nearest-neighbour interaction and calculate exactly the longitudinal spin-spin correlation for a class of excited states. These states are known to play an important role in the perturbative treatment of one-dimensional transverse Ising model with frustrated second-neighbour interaction. To calculate the correlation, we follow the earlier procedure of Wu, use Szego's theorem and also use Fisher-Hartwig conjecture. The result is that the correlation decays algebraically with distance ($n$) as $1/\surd n$ and is oscillatory or non-oscillatory depending on the magnitude of the transverse field.

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Anjan Kumar Chandra, Subinay Dasgupta. 2007-04-13. Spin-spin Correlation in Some Excited States of Transverse Ising Model. https://doi.org/10.1088/1751-8113/40/20/001

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