Collective excitations in double-layer quantum Hall systems.
Collective excitations in double-layer quantum Hall systems.
复制标题
双层量子霍尔系统中的集体激发。
DOI：
10.1103/physrevb.49.17208
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Zhang
中科院分区：
文献类型：
--
作者：
Macdonald;Zhang
我们用单模近似研究了双层量子霍尔系统的集体激发谱。双层同相密度激发类似于单层系统。然而，对于同相密度激发，朗道能级间和朗道内双层模都具有有限的偶极振子强度。后一种跃迁的长波振子强度通过相互作用向上移动了相同的量，与层间库仑耦合成正比。当基态不可压缩时，除非存在自发层间相干，否则内朗道能级反相模存在间隙。我们将我们的结果与基于Chern-Simons-Landau-Ginzburg理论的双层量子霍尔系统的预测进行了比较。
We study the collective excitation spectra of double-layer quantum-Hall systems using the single mode approximation. The double-layer in-phase density excitations are similar to those of a single-layer system. For out-of-phase density excitations, however, both inter-Landau-level and intra-Landau-level double-layer modes have finite dipole oscillator strengths. The oscillator strengths at long wavelengths for the latter transitions are shifted upward by interactions by identical amounts proportional to the interlayer Coulomb coupling. The intra-Landau-level out-of-phase mode has a gap when the ground state is incompressible except in the presence of spontaneous inter-layer coherence. We compare our results with predictions based on the Chern-Simons-Landau-Ginzburg theory for double-layer quantum Hall systems.