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Dynamics of quantum Hall stripes in double-quantum-well systems

R. Cote·H. A. Fertig
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Abstract

The collective modes of stripes in double layer quantum Hall systems are computed using the time-dependent Hartree-Fock approximation. It is found that, when the system possesses spontaneous interlayer coherence, there are two gapless modes, one a phonon associated with broken translational invariance, the other a pseudospin-wave associated with a broken U(1) symmetry. For large layer separations the modes disperse weakly for wavevectors perpendicular to the stripe orientation, indicating the system becomes akin to an array of weakly coupled one-dimensional XY systems. At higher wavevectors the collective modes develop a roton minimum associated with a transition out of the coherent state with further increasing layer separation. A spin wave model of the system is developed, and it is shown that the collective modes may be described as those of a system with helimagnetic ordering.

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R. Cote, H. A. Fertig. 2001-09-05. Dynamics of quantum Hall stripes in double-quantum-well systems. https://doi.org/10.1103/physrevb.65.085321

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