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

Article

关键词: STRONG MAGNETIC-FIELD;    2-DIMENSIONAL WIGNER CRYSTAL;    HIGH LANDAU-LEVELS;    COLLECTIVE MODES;    ELECTRON-GAS;    LIQUID;    SYMMETRY;    SMECTICS;    PHASES;    STATE;   

DOI  :  10.1103/PhysRevB.65.085321

来源: SCIE

【 摘 要 】

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(l) symmetry. For large layer separations the modes disperse weakly for wave vectors perpendicular to the stripe orientation, indicating that the system becomes akin to an array of weakly coupled one-dimensional XY systems. At higher wave vectors 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.

【 授权许可】

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