Roostaei B, Mullen K J, Fertig H A, Simon S H
Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106, USA.
Phys Rev Lett. 2008 Jul 25;101(4):046804. doi: 10.1103/PhysRevLett.101.046804.
We analyze the transport properties of bilayer quantum Hall systems at total filling factor nu=1 in drag geometries as a function of interlayer bias, in the limit where the disorder is sufficiently strong to unbind meron-antimeron pairs, the charged topological defects of the system. We compute the typical energy barrier for these objects to cross incompressible regions within the disordered system using a Hartree-Fock approach, and show how this leads to multiple activation energies when the system is biased. We then demonstrate using a bosonic Chern-Simons theory that in drag geometries current in a single layer directly leads to forces on only two of the four types of merons, inducing dissipation only in the drive layer. Dissipation in the drag layer results from interactions among the merons, resulting in very different temperature dependences for the drag and drive layers, in qualitative agreement with experiment.
我们分析了双层量子霍尔系统在总填充因子 $\nu = 1$ 时，在拖曳几何结构中作为层间偏置函数的输运性质，在无序足够强以至于使系统的带电拓扑缺陷——磁单极子 - 反磁单极子对解离的极限情况下。我们使用哈特里 - 福克方法计算这些物体穿越无序系统内不可压缩区域的典型能量势垒，并展示当系统存在偏置时这如何导致多个激活能。然后我们使用玻色子陈 - 西蒙斯理论证明，在拖曳几何结构中，单层中的电流仅直接对四种类型磁单极子中的两种产生力，仅在驱动层中引起耗散。拖曳层中的耗散源于磁单极子之间的相互作用，导致拖曳层和驱动层的温度依赖性非常不同，这与实验定性一致。
