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Response of incompressible fractional quantum Hall states to magnetic and non-magnetic impurities

Karel Výborný·Christian Müller·Daniela Pfannkuche
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Abstract

Using exact diagonalization we examine the response of several most prominent fractional quantum Hall states to a single local impurity. The 2/3 singlet state is found to be more inert than the polarized one in spite of its smaller incompressibility gap. Based on its spin-spin correlation functions we interpret it as a liquid of electron pairs with opposite spin. A comparison of different types of impurities, non-magnetic and magnetic, is presented.

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Karel Výborný, Christian Müller, Daniela Pfannkuche. 2007-03-05. Response of incompressible fractional quantum Hall states to magnetic and non-magnetic impurities. https://arxiv.org/abs/cond-mat/0703109

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