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تسجيل مستخدم جديدNon-linear Transport in Quantum-Hall Smectics
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A.H. MacDonald
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Recent transport experiments have established that two-dimensional electron systems with high-index partial Landau level filling, $ u^{*} = u - lbrack u rbrack$, have ground states with broken orientational symmetry. In a mean-field theory, the broken symmetry state consists of electron stripes with local filling factor $lbrack u rbrack + 1 $, separated by hole stripes with filling factor $lbrack u rbrack$. We have recently developed a theory of these states in which the electron stripes are treated as one-dimensional electron systems coupled by interactions and described by using a Luttinger liquid model. Among other things, this theory predicts non-linearities of opposite sign in easy and hard direction resistivities. In this article we briefly review our theory, focusing on its predictions for the dependence of non-linear transport exponents on the separation $d$ between the two-dimensional electron system and a co-planar screening layer.
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