Interlayer Phase Coherence and Josephson Effects in Bilayer Quantum Hall Systems
Interlayer Phase Coherence and Josephson Effects in Bilayer Quantum Hall Systems
复制标题
双层量子霍尔系统中的层间相位相干性和约瑟夫森效应
DOI：
10.1140/epjb/e2012-30026-2
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
G. Tsitsishvili and A. Sawada
中科院分区：
文献类型：
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作者：
Z.F. Ezawa;G. Tsitsishvili and A. Sawada
当一个电子被限制在最低朗道能级内时，它的位置仅由引导中心描述，X坐标和Y坐标不相互交换。运动方程不是从动力学哈密顿量推导出来的，而是从空间的非对易性质得出的。在此微观理论的基础上，我们分析了填充因子ν=1时的双层QH系统，结果表明存在层间位相相干。解释说，相位相干性的产生是由于复合玻色子的玻色-爱因斯坦凝聚，复合玻色子是束缚在磁通量子上的单电子。位相相干可以引起约瑟夫森面内电流和约瑟夫森隧道电流，它们和超导体一样是无耗散的。在逆流和阻力实验中，我们证明了约瑟夫森面内电流引起了霍尔阻力的反常行为。此外，我们还研究了输入电流为相干的无耗散隧道电流的条件。我们还预测了当样品在磁场中倾斜时，条件将如何变化。
When an electron is confined within the lowest Landau level, its position is described solely by the guiding center, whoseXandYcoordinates do not commute with one another. The equations of motion do not follow from the kinetic Hamiltonian but from the noncommutative property of the space. Based on this microscopic theory, we analyze the bilayer QH system at the filling factorν= 1, and show that there develops an interlayer phase coherence. It is interpreted that the phase coherence occurs due to the Bose-Einstein condensation of composite bosons, which are single electrons bound to magnetic flux quanta. The phase coherence can induce the Josephson inplane current as well as the Josephson tunneling current, which are dissipationless as in superconductor. We demonstrate that the Josephson inplane current provokes anomalous behaviors in the Hall resistance in counterflow and drag experiments. Furthermore, we investigate the condition on the input current for the tunneling current to be coherent and dissipationless. We predict also how the condition changes when the sample is tilted in the magnetic field.