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Noise spectroscopy and interlayer phase-coherence in bilayer quantum Hall systems

Yogesh N. Joglekar·Alexander V. Balatsky·Allan H. MacDonald
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Abstract

Bilayer quantum Hall systems develop strong interlayer phase-coherence when the distance between layers is comparable to the typical distance between electrons within a layer. The phase-coherent state has until now been investigated primarily via transport measurements. We argue here that interlayer current and charge-imbalance noise studies in these systems will be able to address some of the key experimental questions. We show that the characteristic frequency of current-noise is that of the zero wavevector collective mode, which is sensitive to the degree of order in the system. Local electric potential noise measured in a plane above the bilayer system on the other hand is sensitive to finite-wavevector collective modes and hence to the soft-magnetoroton picture of the order-disorder phase transition.

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Yogesh N. Joglekar, Alexander V. Balatsky, Allan H. MacDonald. 2003-10-29. Noise spectroscopy and interlayer phase-coherence in bilayer quantum Hall systems. https://doi.org/10.1103/physrevlett.92.086803

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